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1.
Int J Syst Evol Microbiol ; 70(12): 6428-6436, 2020 Dec.
Article in English | MEDLINE | ID: mdl-33174828

ABSTRACT

During a bioprospection of bacteria with antimicrobial activity, the actinomycete strain A38T was isolated from a sediment sample of the Carpintero river located in the Gran Piedra Mountains, Santiago de Cuba province (Cuba). This strain was identified as a member of the genus Micromonospora by means of a polyphasic taxonomy study. Strain A38T was an aerobic Gram-positive filamentous bacterium that produced single spores in a well-developed vegetative mycelium. An aerial mycelium was absent. The cell wall contained meso-diaminopimelic acid and the whole-cell sugars were glucose, mannose, ribose and xylose. The major cellular fatty acids were isoC15:0, 10 methyl C17:0, anteiso-C17:0 and iso-C17:0. The predominant menaquinones were MK-10(H4) and MK-10(H6). Phylogenetic analysis of 16S rRNA gene sequences revealed that this strain was closely related to Micromonospora tulbaghiae DSM 45142T (99.5 %), Micromonospora citrea DSM 43903T (99.4 %), Micromonospora marina DSM 45555T (99.4 %), Micromonospora maritima DSM 45782T (99.3 %), Micromonospora sediminicola DSM 45794T (99.3 %), Micromonospora aurantiaca DSM 43813T (99.2 %) and Micromonospora chaiyaphumensis DSM 45246T (99.2 %). The results of OrthoANIu analysis showed the highest similarity to Micromonospora chalcea DSM 43026T (96.4 %). However, the 16S rRNA and gyrB gene sequence-based phylogeny and phenotypic characteristics provided support to distinguish strain A38T as a novel species. On the basis of the results presented here, we propose to classify strain A38T (=LMG 30467T=CECT 30034T) as the type strain of the novel species Micromonospora fluminis sp. nov.


Subject(s)
Geologic Sediments/microbiology , Micromonospora/classification , Phylogeny , Rivers/microbiology , Bacterial Typing Techniques , Base Composition , Cuba , DNA, Bacterial/genetics , Diaminopimelic Acid/chemistry , Fatty Acids/chemistry , Micromonospora/isolation & purification , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA , Vitamin K 2/chemistry
2.
Int J Syst Evol Microbiol ; 70(12): 6172-6179, 2020 Dec.
Article in English | MEDLINE | ID: mdl-33095134

ABSTRACT

An actinomycete, strain D1T, was isolated from a freshwater sediment sample collected from the San Pablo river in the La Risueña community, Santiago de Cuba province, Cuba. The strain was identified as a member of the genus Nocardiopsis by means of a polyphasic taxonomic study. It produced a light yellow non-fragmented substrate mycelium, a white well-developed aerial mycelium and straight to flexuous hyphae. No specific spore chains were observed. Strain D1T contained meso-diaminopimelic acid, no diagnostic sugars, and MK-10(H2), MK-10(H4), MK-10 and MK-10(H6) as predominant menaquinones, but not phosphatidylcholine as diagnostic polar lipid of the genus Nocardiopsis. The predominant fatty acids were iso-C16 : 0, 10-methyl-C18 : 0 and anteiso-C17 : 0. Strain D1T showed the highest degree of 16S rRNA gene sequence similarity to Nocardiopsis synnematoformans DSM 44143T (99.8 %), Nocardiopsis dassonvillei subsp. albirubida NBRC 13392T (99.8 %) and Nocardiopsis dassonvillei subsp. dassonvillei DSM 43111T (99.6 %). A genomic OrthoANIu value between D1T and N. dassonvillei subsp. dassonvillei DSM 43111T of 97.63 % and a dDDH value of 78.9 % indicated that strain D1T should be classified in N. dassonvillei. However, phenotypic characteristics distinguished strain D1T from its nearest neighbour taxon. On basis of these results we propose to classify strain D1T (=LMG 30468T=CECT 30033T) as a representative of a novel subspecies of the genus Nocardiopsis, for which the name Nocardiopsis dassonvillei subsp. crassaminis subsp. nov. is proposed. In addition, the genomic distance between N. dassonvillei subsp. albirubida NBRC 13392T and N. dassonvillei subsp. dassonvillei DSM 43111T as determined through OrthoANIu (93.64 %) and dDDH (53.40 %), along with considerable phenotypic and chemotaxonomic differences reported in earlier studies, indicated that the classification of this taxon as Nocardiopsis alborubida Grund and Kroppenstedt 1990 is to be preferred over its classification as N. dassonvillei subsp. albirubida Evtushenko et al. 2000.


Subject(s)
Fresh Water/microbiology , Geologic Sediments/microbiology , Nocardiopsis/classification , Phylogeny , Bacterial Typing Techniques , Base Composition , Cuba , DNA, Bacterial/genetics , Diaminopimelic Acid/chemistry , Fatty Acids/chemistry , Nocardiopsis/isolation & purification , Nucleic Acid Hybridization , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA , Vitamin K 2/chemistry
3.
Front Microbiol ; 10: 2556, 2019.
Article in English | MEDLINE | ID: mdl-31781066

ABSTRACT

Comparative analysis of partial gyrB, recA, and gltB gene sequences of 84 Pandoraea reference strains and field isolates revealed several clusters that included no taxonomic reference strains. The gyrB, recA, and gltB phylogenetic trees were used to select 27 strains for whole-genome sequence analysis and for a comparative genomics study that also included 41 publicly available Pandoraea genome sequences. The phylogenomic analyses included a Genome BLAST Distance Phylogeny approach to calculate pairwise digital DNA-DNA hybridization values and their confidence intervals, average nucleotide identity analyses using the OrthoANIu algorithm, and a whole-genome phylogeny reconstruction based on 107 single-copy core genes using bcgTree. These analyses, along with subsequent chemotaxonomic and traditional phenotypic analyses, revealed the presence of 17 novel Pandoraea species among the strains analyzed, and allowed the identification of several unclassified Pandoraea strains reported in the literature. The genus Pandoraea has an open pan genome that includes many orthogroups in the 'Xenobiotics biodegradation and metabolism' KEGG pathway, which likely explains the enrichment of these species in polluted soils and participation in the biodegradation of complex organic substances. We propose to formally classify the 17 novel Pandoraea species as P. anapnoica sp. nov. (type strain LMG 31117T = CCUG 73385T), P. anhela sp. nov. (type strain LMG 31108T = CCUG 73386T), P. aquatica sp. nov. (type strain LMG 31011T = CCUG 73384T), P. bronchicola sp. nov. (type strain LMG 20603T = ATCC BAA-110T), P. capi sp. nov. (type strain LMG 20602T = ATCC BAA-109T), P. captiosa sp. nov. (type strain LMG 31118T = CCUG 73387T), P. cepalis sp. nov. (type strain LMG 31106T = CCUG 39680T), P. commovens sp. nov. (type strain LMG 31010T = CCUG 73378T), P. communis sp. nov. (type strain LMG 31110T = CCUG 73383T), P. eparura sp. nov. (type strain LMG 31012T = CCUG 73380T), P. horticolens sp. nov. (type strain LMG 31112T = CCUG 73379T), P. iniqua sp. nov. (type strain LMG 31009T = CCUG 73377T), P. morbifera sp. nov. (type strain LMG 31116T = CCUG 73389T), P. nosoerga sp. nov. (type strain LMG 31109T = CCUG 73390T), P. pneumonica sp. nov. (type strain LMG 31114T = CCUG 73388T), P. soli sp. nov. (type strain LMG 31014T = CCUG 73382T), and P. terrigena sp. nov. (type strain LMG 31013T = CCUG 73381T).

4.
Int J Syst Evol Microbiol ; 69(10): 3068-3073, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31310199

ABSTRACT

The taxonomic position of 'Actinomadura roseorufa' LMG 30035T, a semduramicin-producing mutant of strain ATCC 53666P, which was isolated from a soil sample collected in Yamae Village, Kamamoto, Japan, was clarified in the present study using a polyphasic approach. This Gram-positive, aerobic actinomycete formed a well-developed, extensively branched, non-fragmenting substrate and aerial mycelia which differentiated into single, smooth-appearing spores. Based on analysis of nearly complete 16S rRNA gene sequence, strain LMG 30035T was found to be closely related to the type strains of Actinomadura fibrosa ATCC 49459T (98.88 %) and Actinomadura formosensis JCM 7474T (98.82 %) (pairwise similarity values in parentheses). Digital DNA-DNA hybridisation experiments revealed unambiguously that strain LMG 30035T represents a novel Actinomadura species (OrthoANIu values less than 83.1 %; dDDH values less than 27.2 % with type strains of validly named Actinomadura species). Analysis of the cell wall revealed the presence of meso-diaminopimelic acid in the peptidoglycan. The whole-cell sugars were glucose, madurose, galactose, ribose and rhamnose. The major polar lipids included phosphatidylinositol and diphosphatidylglycerol. The predominant menaquinones were MK-9(H6), MK-9(H8), MK-9(H4) and MK-9(H2). The major fatty acids were C16 : 00, 10-methyl C18 : 0, C18 : 1 ω9c and C18 : 00. The DNA G+C content of its genome was 72.5 mol%. In summary, these characteristics distinguish strain LMG 30035T from validly named species of the genus Actinomadura, and therefore, we propose to classify this strain formally as the novel species Actinomadura roseirufa sp. nov. with LMG 30035T (=CECT 9808T,=ATCC 53664T) as the type strain.


Subject(s)
Actinobacteria/classification , Nigericin/analogs & derivatives , Phylogeny , Soil Microbiology , Actinobacteria/isolation & purification , Bacterial Typing Techniques , Base Composition , Cell Wall/chemistry , DNA, Bacterial/genetics , Diaminopimelic Acid/chemistry , Fatty Acids/chemistry , Ionophores , Japan , Nigericin/metabolism , Nucleic Acid Hybridization , Peptidoglycan/chemistry , Phospholipids/chemistry , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA , Vitamin K 2/analogs & derivatives , Vitamin K 2/chemistry
5.
Int J Syst Evol Microbiol ; 67(10): 3752-3758, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28895512

ABSTRACT

Strain EPL6T, a Gram-negative, motile, short rod was isolated from a propanil and 3,4-dichloroaniline enrichment culture produced from rice paddy soil. Based on the analyses of the 16S rRNA gene sequence, strain EPL6T was observed to be a member of the family Comamonadaceae, sharing the highest pairwise identity with type strains of the species Alicycliphilus denitrificans K601T (96.8 %) and Melaminivora alkalimesophila CY1T (96.8 %). Strain EPL6T was able to grow in a temperature range of 15-37 °C, pH 6-9 and in the presence of up to 4 % (w/v) NaCl and tested positive for catalase and oxidase reactions. The major respiratory quinone was Q8. The genomic DNA had a G+C content of 69.4±0.9 mol%. The major polar lipids were phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol, and the major fatty acid methyl esters comprised C16 : 0, C18 : 1ω7c and summed feature 3 (C16 : 1ω7c/iso-C15 : 0 2-OH). Comparison of the genome sequence of strain EPL6T and of its closest neighbours, Melaminivora alkalimesophila CY1T and Alicycliphilus denitrificans K601T, yielded values of ANI ≤84.1 % and of AAI ≤80.3 %. Therefore, the genetic, phylogenetic, phenotypic and chemotaxonomic characteristics support the classification of this organism into a new taxon. Considering the genetic divergence of strain EPL6T from the type strains of the closest species, which belong to distinct genera, we propose a new genus within the family Comamonadaceae, named Oryzisolibacter propanilivorax gen. nov., sp. nov., represented by the isolate EPL6T as the type strain of the species (=LMG 28427T=CECT 8927T).


Subject(s)
Phylogeny , Propanil/metabolism , Soil Microbiology , Bacterial Typing Techniques , Base Composition , Comamonadaceae/classification , Comamonadaceae/genetics , Comamonadaceae/isolation & purification , DNA, Bacterial/genetics , Fatty Acids/chemistry , Oryza , Phospholipids/chemistry , Portugal , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA , Ubiquinone/chemistry
6.
Int J Syst Evol Microbiol ; 67(5): 1415-1421, 2017 05.
Article in English | MEDLINE | ID: mdl-28141505

ABSTRACT

The taxonomic position of two isolates belonging to the genus Sphingobacterium was determined. The first isolate, R-53603T, was obtained from purulent discharge from the toe of a cellulitis patient in Kuwait. Comparative 16S rRNA gene sequence analysis revealed 99.87 % similarity of R-53603T with environmental isolate P031 (=R-53745) originating from activated sludge in Singapore. The two isolates were phylogenetically positioned on the same sub-branch. Highest 16S rRNA gene sequence similarity was found with the type strains of Sphingobacterium mizutaii (98.23 %), Sphingobacterium lactis (97.78 %) and Sphingobacterium daejeonense (97.14 %). DNA-DNA hybridizations revealed <70 % relatedness between the two isolates and the type strains of the close phylogenetic neighbours S. mizutaii(18.0-24.5 %), S. lactis(20.3-25.9 %) and S. daejeonense(13.2-20.0 %). The high relative contribution of iso-C15 : 0, iso-C17 : 0 3-OH and summed feature 3 (iso-C15 : 0 2-OH and/or C16 : 1ω7c) in the cellular fatty acid profiles of R-53603T and R-53745, the presence of sphingophospholipids, MK-7 as the dominant menaquinone and phosphatidylethanolamine as the major polar lipid in strain R-53603T are typical chemotaxonomic characteristics for members of the genus Sphingobacterium. Phenotypic features most useful for differentiation of the two novel strains from the most closely related species S. mizutaii include growth on MacConkey agar, and utilization of stachyose, guanidine HCl and lithium chloride in Biolog GEN III tests. Strains R-53603T and R-53745 thus represent a novel species, for which the name Sphingobacterium cellulitidis sp. nov. is proposed. The type strain is R-53603T (=LMG 28764T=DSM 102028T).


Subject(s)
Cellulitis/microbiology , Phylogeny , Sewage/microbiology , Sphingobacterium/classification , Bacterial Typing Techniques , Base Composition , DNA, Bacterial/genetics , Fatty Acids/analysis , Humans , Kuwait , Nucleic Acid Hybridization , Phospholipids/chemistry , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA , Singapore , Sphingobacterium/genetics , Sphingobacterium/isolation & purification , Toes/microbiology , Vitamin K 2/analogs & derivatives , Vitamin K 2/chemistry
7.
PLoS One ; 10(4): e0123933, 2015.
Article in English | MEDLINE | ID: mdl-25905625

ABSTRACT

Understanding the symbiotic relationship between gut microbes and their animal host requires characterization of the core microbiota across populations and in time. Especially in captive populations of endangered wildlife species such as the cheetah (Acinonyx jubatus), this knowledge is a key element to enhance feeding strategies and reduce gastrointestinal disorders. In order to investigate the temporal stability of the intestinal microbiota in cheetahs under human care, we conducted a longitudinal study over a 3-year period with bimonthly faecal sampling of 5 cheetahs housed in two European zoos. For this purpose, an integrated 16S rRNA DGGE-clone library approach was used in combination with a series of real-time PCR assays. Our findings disclosed a stable faecal microbiota, beyond intestinal community variations that were detected between zoo sample sets or between animals. The core of this microbiota was dominated by members of Clostridium clusters I, XI and XIVa, with mean concentrations ranging from 7.5-9.2 log10 CFU/g faeces and with significant positive correlations between these clusters (P<0.05), and by Lactobacillaceae. Moving window analysis of DGGE profiles revealed 23.3-25.6% change between consecutive samples for four of the cheetahs. The fifth animal in the study suffered from intermediate episodes of vomiting and diarrhea during the monitoring period and exhibited remarkably more change (39.4%). This observation may reflect the temporary impact of perturbations such as the animal's compromised health, antibiotic administration or a combination thereof, which temporarily altered the relative proportions of Clostridium clusters I and XIVa. In conclusion, this first long-term monitoring study of the faecal microbiota in feline strict carnivores not only reveals a remarkable compositional stability of this ecosystem, but also shows a qualitative and quantitative similarity in a defined set of faecal bacterial lineages across the five animals under study that may typify the core phylogenetic microbiome of cheetahs.


Subject(s)
Acinonyx/microbiology , Feces/microbiology , Microbiota/genetics , Animals , Animals, Wild , Animals, Zoo/microbiology , Clostridium/genetics , Gastrointestinal Diseases/microbiology , Lactobacillaceae/genetics , Longitudinal Studies , Phylogeny , RNA, Ribosomal, 16S/genetics
8.
Int J Food Microbiol ; 185: 7-16, 2014 Aug 18.
Article in English | MEDLINE | ID: mdl-24927398

ABSTRACT

A study monitoring lactic acid bacteria contamination was conducted in a company producing fresh, minimally processed, packaged and ready-to-eat (RTE) vegetable salads (stored at 4°C) in order to investigate the reason for high psychrotrophic LAB levels in the products at the end of shelf-life. Initially, high microbial counts exceeding the established psychrotrophic thresholds (>10(7)-10(8)CFU/g) and spoilage manifestations before the end of the shelf-life (7days) occurred in products containing an assortment of sliced and diced vegetables, but within a one year period these spoilage defects became prevalent in the entire processing plant. Environmental sampling and microbiological analyses of the raw materials and final products throughout the manufacturing process highlighted the presence of high numbers of Leuconostoc spp. in halved and unseeded, fresh sweet bell peppers provided by the supplier. A combination of two DNA fingerprinting techniques facilitated the assessment of the species diversity of LAB present in the processing environment along with the critical point of their introduction in the production facility. Probably through air mediation and surface adhesion, mainly members of the strictly psychrotrophic species Leuconostoc gelidum subsp. gasicomitatum and L. gelidum subsp. gelidum were responsible for the cross-contamination of every vegetable handled within the plant.


Subject(s)
Food Industry/methods , Food Microbiology , Leuconostoc/isolation & purification , Vegetables/microbiology , Biodiversity , Capsicum/microbiology , Colony Count, Microbial , DNA Fingerprinting , Food Industry/standards , Genes, Bacterial/genetics , Leuconostoc/genetics
9.
Int J Syst Evol Microbiol ; 64(Pt 6): 2003-2008, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24623656

ABSTRACT

Two Gram-negative, rod-shaped bacteria were isolated from agricultural soils in Córdoba province in central Argentina. Their 16S rRNA gene sequences demonstrated that they belong to the genus Burkholderia, with Burkholderia zhejiangensis as most closely related formally named species; this relationship was confirmed through comparative gyrB sequence analysis. Whole-cell fatty acid analysis supported their assignment to the genus Burkholderia. Burkholderia sp. strain YI23, for which a whole-genome sequence is available, represents the same taxon, as demonstrated by its highly similar 16S rRNA (100% similarity) and gyrB (99.1-99.7%) gene sequences. The results of DNA-DNA hybridization experiments and physiological and biochemical characterization further substantiated the genotypic and phenotypic distinctiveness of the Argentinian soil isolates, for which the name Burkholderia cordobensis sp. nov. is proposed, with strain MMP81(T) ( = LMG 27620(T) = CCUG 64368(T)) as the type strain.


Subject(s)
Burkholderia/classification , Phylogeny , Soil Microbiology , Agriculture , Argentina , Bacterial Typing Techniques , Base Composition , Burkholderia/genetics , Burkholderia/isolation & purification , DNA Gyrase/genetics , DNA, Bacterial/genetics , Fatty Acids/chemistry , Genotype , Molecular Sequence Data , Nucleic Acid Hybridization , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA
10.
Food Microbiol ; 39: 61-7, 2014 May.
Article in English | MEDLINE | ID: mdl-24387853

ABSTRACT

Previously, a considerable underestimation (+0.5-3.2 log CFU/g) on the contamination levels of psychrotrophic lactic acid bacteria (LAB) was observed for 33 retail, packaged food products stored at chilling temperature when the mesophilic enumeration technique was implemented as reference shelf-life parameter. In the present study, the microbial diversity of the dominant psychrotrophic LAB recovered after incubation of plates at 22 °C for 5 days was determined using a polyphasic taxonomic approach. A total of 212 LAB isolates were identified using a combination of rep-PCR fingerprinting, amplified fragment length polymorphism (AFLP) analysis and pheS gene sequencing. Leuconostoc gasicomitatum, Leuconostoc gelidum, Leuconostoc spp., Lactococcus piscium and Lactobacillus algidus proved to be the most competent and predominant species that may go undetected by the widely applied mesophilic enumeration protocols (ISO 4833:2003 and ISO 15214:1998). This study has assessed the interspecific variation among potential spoilage LAB, and highlights the significance of implementing a reference shelf-life parameter based on the enumeration of the total psychrotrophic bacterial load for industrial microbiological routine analyses.


Subject(s)
Lactococcus/isolation & purification , Leuconostoc/isolation & purification , Meat Products/microbiology , Meat/microbiology , Vegetables/microbiology , Animals , Bacterial Typing Techniques , Belgium , Cattle , Cold Temperature , Food Packaging , Food Storage , Lactococcus/classification , Lactococcus/genetics , Lactococcus/growth & development , Leuconostoc/classification , Leuconostoc/genetics , Leuconostoc/growth & development , Swine
11.
Int J Syst Evol Microbiol ; 63(Pt 5): 1754-1759, 2013 May.
Article in English | MEDLINE | ID: mdl-22941299

ABSTRACT

A species diversity study of lactic acid bacteria occurring in traditional Vietnamese nem chua yielded an isolate, LMG 26767(T), that could not be assigned to a species with a validly published name. The isolate was initially investigated by 16S rRNA gene sequence analysis, which revealed that it belonged to the genus Lactobacillus, with Lactobacillus manihotivorans and Lactobacillus camelliae as the closest relatives (98.9 % and 96.9 % gene sequence similarity to the type strains, respectively). Comparative (GTG)5-PCR genomic fingerprinting confirmed the unique taxonomic status of the novel strain. DNA-DNA hybridization experiments, DNA G+C content determination, sequence analysis of the phenylalanyl-tRNA synthase (pheS) gene, and physiological and biochemical characterization demonstrated that strain LMG 26767(T) represents a novel species, for which the name Lactobacillus porcinae sp. nov. is proposed; the type strain is LMG 26767(T) ( = CCUG 62266(T)). Biochemically, L. porcinae can be distinguished from L. manihotivorans and L. camelliae by its carbohydrate fermentation profile, absence of growth at 45 °C, and production of d- and l-lactate as end products of glucose metabolism.


Subject(s)
Food Microbiology , Lactobacillus/classification , Meat/microbiology , Phylogeny , Animals , Bacterial Typing Techniques , Base Composition , DNA, Bacterial/genetics , Fermentation , Lactobacillus/genetics , Lactobacillus/isolation & purification , Molecular Sequence Data , Nucleic Acid Hybridization , Peptidoglycan/analysis , Phenylalanine-tRNA Ligase/genetics , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA , Swine , Vietnam
12.
Int J Syst Evol Microbiol ; 58(Pt 12): 2687-93, 2008 Dec.
Article in English | MEDLINE | ID: mdl-19060041

ABSTRACT

Four Gram-positive, aerobic, non-sporulating, rod-shaped bacteria isolated from the surface microflora of Reblochon cheese at the late stage of ripening had chemotaxonomic properties characteristic of members of the family Microbacteriaceae. The isolates had virtually identical SDS-PAGE whole-organism protein patterns, shared many chemical and phenotypic characteristics and formed an independent branch in the Microbacteriaceae 16S rRNA gene tree that was most closely related to the type strains of Mycetocola species. The new isolates had chemotaxonomic properties consistent with their classification in the genus Mycetocola but were readily distinguished from recognized members of this taxon based on DNA-DNA relatedness, whole-organism protein and phenotypic data. The combined genotypic and phenotypic data indicate that the isolates should be classified in the genus Mycetocola as members of a novel species, for which the name Mycetocola reblochoni sp. nov. is proposed. The type strain is LMG 22367(T) (=R-20377(T) =BRB-1L41(T) =DSM 18580(T)).


Subject(s)
Actinomycetales/classification , Actinomycetales/physiology , Cheese/microbiology , Actinomycetales/chemistry , Actinomycetales/genetics , Electrophoresis, Polyacrylamide Gel , Fatty Acids/analysis , Molecular Sequence Data , Phylogeny , RNA, Ribosomal, 16S/genetics , Species Specificity , Vitamin K 2/analysis
13.
Int J Syst Evol Microbiol ; 58(Pt 12): 2799-802, 2008 Dec.
Article in English | MEDLINE | ID: mdl-19060061

ABSTRACT

Five isolates that produced large amounts of butyrate were obtained in the course of a study on the butyrate-producing microbiota from the caecal content of a 4-week-old broiler chicken. The five isolates were virtually indistinguishable in biochemical and genetic terms, suggesting that they were derived from a single bacterial clone colonizing this habitat. A phylogenetic analysis based on 16S rRNA gene sequences demonstrated that the five isolates represented a unique lineage within the Clostridium leptum subgroup of the clostridia, with Eubacterium desmolans as the closest phylogenetic neighbour (about 93 % similarity). These data indicate that the five novel isolates represent a single novel species within a novel genus, for which we propose the name Butyricicoccus pullicaecorum gen. nov., sp. nov. The type strain of Butyricicoccus pullicaecorum is 25-3(T) (=LMG 24109(T) =CCUG 55265(T)). The DNA G+C content of strain 25-3(T) was 54.5 mol% .


Subject(s)
Butyrates/metabolism , Chickens/microbiology , Gastrointestinal Contents/microbiology , Gram-Positive Endospore-Forming Rods/classification , Gram-Positive Endospore-Forming Rods/physiology , Anaerobiosis , Animals , Fermentation , Gram-Positive Endospore-Forming Rods/genetics , Gram-Positive Endospore-Forming Rods/metabolism , Molecular Sequence Data , Phylogeny , RNA, Ribosomal, 16S/genetics , Species Specificity
14.
Appl Environ Microbiol ; 74(14): 4247-55, 2008 Jul.
Article in English | MEDLINE | ID: mdl-18487397

ABSTRACT

The intraspecific relationships among a collection of Enterococcus faecium isolates comprising probiotic cultures and human clinical isolates were investigated through the combined use of two high-resolution DNA-fingerprinting techniques. In addition, the incidences of antimicrobial resistance and virulence traits were investigated. A total of 128 E. faecium isolates from human clinical or nonclinical sources or used as probiotic cultures were subjected to fluorescent amplified fragment length polymorphism (FAFLP) fingerprinting and pulsed-field gel electrophoresis (PFGE) analysis of SmaI macrorestriction patterns. Susceptibilities to 16 antimicrobial agents were tested using broth microdilution, and the presence of the corresponding resistance genes was investigated using PCR. Multiplex PCR was used to detect the presence of the enterococcal virulence genes asa1, gelE, cylA, esp, and hyl. The results of the study showed that two intraspecific genomic groups (I and II) were obtained in FAFLP analysis. PFGE analysis demonstrated high variability within these two groups but also indicated that some probiotic cultures were indistinguishable and that a number of clinical isolates may be reisolations of commercial probiotic cultures. Compared to group II, which contained the majority of the probiotic isolates and fewer human clinical isolates, higher phenotypic and genotypic resistance frequencies were observed in group I. Two probiotic isolates were phenotypically resistant to erythromycin, one of which contained an erm(B) gene that was not transferable to enterococcal recipients. None of the probiotic E. faecium isolates demonstrated the presence of the tested virulence genes. The previously reported observation that E. faecium consists of two intraspecific genomic groups was further substantiated by FAFLP fingerprinting of 128 isolates. In combination with antimicrobial resistance and virulence testing, this grouping might represent an additional criterion in assessing the safety of new potential probiotic E. faecium isolates.


Subject(s)
Drug Resistance, Bacterial/genetics , Enterococcus faecium/classification , Enterococcus faecium/genetics , Probiotics/classification , Virulence Factors/genetics , Amplified Fragment Length Polymorphism Analysis , Anti-Bacterial Agents/pharmacology , Bacterial Typing Techniques , Cluster Analysis , Electrophoresis, Gel, Pulsed-Field , Enterococcus faecium/drug effects , Feces/microbiology , Food Microbiology , Gene Frequency , Genetic Variation , Genotype , Humans , Microbial Sensitivity Tests , Phenotype , Polymerase Chain Reaction
15.
FEMS Immunol Med Microbiol ; 49(2): 192-6, 2007 Mar.
Article in English | MEDLINE | ID: mdl-17328753

ABSTRACT

Fifteen lactic acid bacterial strains were isolated from blood cultures from 15 different patients in the Faculty Hospital in Brno, Czech Republic. All strains were identified using biochemical tests and repetitive PCR using the (GTG)5 primer. Doubtful identification results were confirmed by whole-cell protein analysis. The strains were assigned to the genera Lactobacillus (eight strains representing seven species), Leuconostoc (six strains representing four species) and Weissella (one strain). Antibiotic susceptibility testing was performed using the E-test and revealed high-level resistance to cotrimoxazol, metronidazole, vancomycin and teicoplanin, but nearly all strains were susceptible to erythromycin, clindamycin, ampicillin and penicillin.


Subject(s)
Bacteremia/microbiology , Blood/microbiology , Gram-Positive Bacteria/isolation & purification , Gram-Positive Bacterial Infections/microbiology , Lactobacillus/isolation & purification , Leuconostoc/isolation & purification , Adolescent , Adult , Aged , Aged, 80 and over , Anti-Bacterial Agents/pharmacology , Bacterial Proteins/analysis , Bacterial Typing Techniques , Child , Child, Preschool , Czech Republic , DNA, Bacterial/genetics , Female , Gram-Positive Bacteria/genetics , Gram-Positive Bacteria/physiology , Hospitals, University , Humans , Infant , Lactobacillus/genetics , Lactobacillus/physiology , Leuconostoc/genetics , Leuconostoc/physiology , Male , Microbial Sensitivity Tests , Middle Aged , Polymerase Chain Reaction , Repetitive Sequences, Nucleic Acid/genetics
16.
Int J Syst Evol Microbiol ; 56(Pt 11): 2523-2527, 2006 Nov.
Article in English | MEDLINE | ID: mdl-17082384

ABSTRACT

The taxonomic position of six Lactobacillus amylophilus strains isolated from swine waste-corn fermentations was reinvestigated. All strains were included in a multilocus sequence analysis (MLSA) study for species identification of Lactobacillus using the genes encoding the phenylalanyl-tRNA synthase alpha subunit (pheS) and RNA polymerase alpha subunit (rpoA). Partial pheS and rpoA gene sequences showed that strains LMG 11400 and NRRL B-4435 represent a separate lineage that is distantly related to the type strain of L. amylophilus, LMG 6900T, and to three other strains of the species. The MLSA data showed that the two strains LMG 11400 and NRRL B-4435 constituted a distinct cluster, sharing 100% pheS and rpoA gene sequence similarity. The other reference strains clustered together with the type strain of L. amylophilus, LMG 6900T, and were clearly differentiated from strains LMG 11400 and NRRL B-4435 (80 and 89% pheS and rpoA gene sequence similarity, respectively). The 16S rRNA gene sequences of the latter two strains are 100% identical, with the nearest phylogenetic neighbour L. amylophilus LMG 6900T showing only 97.2% 16S rRNA gene sequence similarity. Further polyphasic taxonomic study based on whole-cell protein fingerprinting, DNA-DNA hybridization and biochemical features demonstrated that the two strains represent a single, novel Lactobacillus species, for which the name Lactobacillus amylotrophicus sp. nov. is proposed. The type strain is LMG 11400T (=NRRL B-4436T=DSM 20534T).


Subject(s)
Lactobacillus/classification , Animal Husbandry , Bacterial Proteins/genetics , Bacterial Typing Techniques , Carbohydrate Metabolism , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , DNA-Directed RNA Polymerases/genetics , Electrophoresis, Polyacrylamide Gel , Genes, rRNA , Industrial Waste , Lactobacillus/cytology , Lactobacillus/isolation & purification , Lactobacillus/physiology , Molecular Sequence Data , Nucleic Acid Hybridization , Phenylalanine-tRNA Ligase/genetics , Phylogeny , Protein Subunits/genetics , Proteome/analysis , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA , Sequence Homology, Nucleic Acid
17.
Int J Syst Evol Microbiol ; 56(Pt 7): 1681-1683, 2006 Jul.
Article in English | MEDLINE | ID: mdl-16825650

ABSTRACT

The applicability of a multilocus sequence analysis (MLSA)-based identification system for lactobacilli was evaluated. Two housekeeping genes that code for the phenylalanyl-tRNA synthase alpha-subunit (pheS) and RNA polymerase alpha-subunit (rpoA) were sequenced and analysed for members of the Lactobacillus salivarius species group. The type strains of Lactobacillus acidipiscis and Lactobacillus cypricasei were investigated further using a third gene that encodes the alpha-subunit of ATP synthase (atpA). The MLSA data revealed close relatedness between L. acidipiscis and L. cypricasei, with 99.8-100 % pheS, rpoA and atpA gene sequence similarities. Comparison of the 16S rRNA gene sequences of the type strains of the two species confirmed the close relatedness (99.8 % gene sequence similarity) between the two taxa. Similar phenotypes and high DNA-DNA binding values in the range of 84 to 97.5 % confirmed that L. acidipiscis and L. cypricasei are synonymous species. On the basis of the present study, it is proposed that Lactobacillus cypricasei is a later heterotypic synonym of Lactobacillus acidipiscis.


Subject(s)
Lactobacillus/classification , Bacterial Proteins/genetics , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , DNA-Directed RNA Polymerases/genetics , Lactobacillus/genetics , Mitochondrial Proton-Translocating ATPases/genetics , Molecular Sequence Data , Nucleic Acid Hybridization , Phenylalanine-tRNA Ligase/genetics , Phylogeny , Protein Subunits/genetics , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA , Sequence Homology, Nucleic Acid
18.
Int J Syst Evol Microbiol ; 56(Pt 3): 577-581, 2006 Mar.
Article in English | MEDLINE | ID: mdl-16514030

ABSTRACT

Three enterococci constituted two aberrant branches after numerical analysis of (GTG)5-PCR fingerprints: analogous patterns were found for two water isolates, strains W213 and W442T, and a separate position was found for an isolate from the gut of a termite, strain LMG 8895T. 16S rRNA gene sequence analysis classified all three strains in the Enterococcus faecalis species group. Further sequencing analysis of the housekeeping gene pheS (encoding the phenylalanyl-tRNA synthase alpha-subunit) and whole-cell-protein analysis confirmed a distinct position for the two water isolates and the termite strain, respectively. DNA-DNA hybridization experiments and distinct phenotypic features between the strains studied and representatives of the E. faecalis species group confirmed novel species status, respectively, for the two water isolates, strains W213 and W442T, and for strain LMG 8895T. The names Enterococcus silesiacus sp. nov. and Enterococcus termitis sp. nov. are proposed for the novel taxa, with W442T (= CCM 7319T = LMG 23085T) and LMG 8895T (= CCM 7300T) as the respective type strains.


Subject(s)
Enterococcus/classification , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , DNA, Ribosomal/chemistry , Enterococcus/genetics , Enterococcus/physiology , Nucleic Acid Hybridization , Phenotype , Phylogeny , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA
19.
J Microbiol Methods ; 66(3): 410-33, 2006 Sep.
Article in English | MEDLINE | ID: mdl-16522336

ABSTRACT

This study examines how the discriminatory power of an automated bacterial whole-cell fatty acid identification system can be significantly enhanced by exploring the vast amounts of information accumulated during 15 years of routine gas chromatographic analysis of the fatty acid content of aerobic bacteria. Construction of a global peak occurrence histogram based upon a large fatty acid database is shown to serve as a highly informative tool for assessing the delineation of the naming windows used during the automatic recognition of fatty acid compounds. Along the lines of this data mining application, it is suggested that several naming windows of the Sherlock MIS TSBA50 peak naming method may need to be re-evaluated in order to fit more closely with the bulk of observed fatty acid profiles. At the same time, the global peak occurrence histogram has put forward the delineation of 32 new peak naming windows, accounting for a 26% increase in the total number of fatty acid features taken into account for bacterial identification. By scrutinizing the relationships between the newly delineated naming windows and the many taxonomic units covered within a proprietary fatty acid database, all new naming windows were proven to correspond with stable features of some specific groups of microorganisms. This latter analysis clearly underscores the impact of incorporating the new fatty acid compounds for improving the resolution of the bacterial identification system and endorses the applicability of knowledge discovery in databases within the field of microbiology.


Subject(s)
Bacteria, Aerobic/chemistry , Fatty Acids/analysis , Bacteria, Aerobic/classification , Chromatography, Gas , Databases, Factual
20.
Int J Syst Evol Microbiol ; 56(Pt 2): 413-416, 2006 Feb.
Article in English | MEDLINE | ID: mdl-16449449

ABSTRACT

The taxonomic relatedness between the species Enterococcus casseliflavus and Enterococcus flavescens and between Enterococcus italicus and Enterococcus saccharominimus was investigated. Literature data had already indicated the synonymy between E. casseliflavus and E. flavescens, but this observation had not been formally published. Additional evidence that the two taxa represent a single species was provided by comparison of the partial sequences for three housekeeping genes, phenylalanyl-tRNA synthase alpha subunit (pheS), RNA polymerase alpha subunit (rpoA) and the alpha subunit of ATP synthase (atpA). Additional genomic data derived from DNA-DNA hybridization demonstrated that the two species are synonymous. For E. italicus and E. saccharominimus, two recently described taxa, a high 16S rRNA gene sequence similarity of >99% and analogous phenotypic features indicated a close taxonomic relatedness. The same multilocus sequence analysis scheme for the three housekeeping genes was also applied for E. italicus and E. saccharominimus and indicated possible conspecificity, an observation that was also confirmed by a high DNA-DNA hybridization value (>or=78%). Data from the present study led to the proposal that E. flavescens should be reclassified as a later synonym of E. casseliflavus and that E. saccharominimus should be reclassified as a later synonym of E. italicus.


Subject(s)
Enterococcus/classification , Enterococcus/genetics , Bacterial Proteins/genetics , Bacterial Typing Techniques , DNA, Bacterial/analysis , DNA, Ribosomal/analysis , DNA-Directed RNA Polymerases/genetics , Genes, rRNA , Molecular Sequence Data , Nucleic Acid Hybridization , Phenotype , Phylogeny , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA , Species Specificity
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