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1.
Biotechnol Lett ; 43(9): 1715-1722, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34003399

RESUMO

OBJECTIVE: Marine actinomycetes from the genus Salinispora have an unexploited biotechnological potential. To accurately estimate their application potential however, data on their cultivation, including biomass growth kinetics, are needed but only incomplete information is currently available. RESULTS: This work provides some insight into the effect of temperature, salinity, nitrogen source, glucose concentration and oxygen supply on growth rate, biomass productivity and yield of Salinispora tropica CBN-440T. The experiments were carried out in unbaffled shake flasks and agitated laboratory-scale bioreactors. The results show that the optimum growth temperature lies within the range 28-30 °C, salinity is close to sea water and the initial glucose concentration is around 10 g/L. Among tested nitrogen sources, yeast extract and soy peptone proved to be the most suitable. The change from unbaffled to baffled flasks increased the volumetric oxygen transfer coefficient (kLa) as did the use of agitated bioreactors. The highest specific growth rate (0.0986 h-1) and biomass productivity (1.11 g/L/day) were obtained at kLa = 28.3 h-1. A further increase in kLa was achieved by increasing stirrer speed, but this led to a deterioration in kinetic parameters. CONCLUSIONS: Improvement of S. tropica biomass growth kinetics of was achieved mainly by identifying the most suitable nitrogen sources and optimizing kLa in baffled flasks and agitated bioreactors.


Assuntos
Técnicas de Cultura Celular por Lotes/métodos , Reatores Biológicos/microbiologia , Micromonosporaceae/crescimento & desenvolvimento , Biomassa , Meios de Cultura/química , Glucose/metabolismo , Fenômenos Mecânicos , Nitrogênio/metabolismo , Oxigênio/metabolismo , Salinidade , Temperatura
2.
Mol Genet Genomics ; 295(6): 1529-1535, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32894358

RESUMO

Lanthipeptides are a subgroup of ribosomally encoded and post-translationally modified peptides (RiPPs) which frequently possess potent biological activity. Here we provide the first comprehensive bioinformatic analysis of the lanthipeptide-producing capability of the Salinispora genus, a marine actinomycete. One hundred twenty-two Salinispora arenicola, tropica, and pacifica genomic sequences were analyzed for lanthipeptide gene clusters, and the resulting 182 clusters were divided into seven groups based on sequence similarities. Group boundaries were defined based on LanB and LanM sequences with greater than 80% similarity within groups. Of the seven groups, six are predicted to encode class I lanthipeptides while only one group is predicted to encode class II lanthipeptides. Leader and core peptides were predicted for each cluster along with the number of possible lanthionine bridges. Notably, all of the predicted products of these clusters would represent novel lanthipeptide scaffolds. Of the 122 Salinispora genomes analyzed in this study, 92% contained at least one lanthipeptide gene cluster suggesting that Salinispora is a rich, yet untapped, source of lanthipeptides.


Assuntos
Alanina/análogos & derivados , Proteínas de Bactérias/metabolismo , Genoma Bacteriano , Micromonosporaceae/metabolismo , Fragmentos de Peptídeos/metabolismo , Sulfetos/metabolismo , Alanina/isolamento & purificação , Alanina/metabolismo , Proteínas de Bactérias/genética , Genômica , Micromonosporaceae/genética , Micromonosporaceae/crescimento & desenvolvimento , Fragmentos de Peptídeos/isolamento & purificação , Sulfetos/isolamento & purificação
3.
Molecules ; 25(3)2020 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-31991684

RESUMO

Pilidiella granati, also known as Coniella granati, is the etiological agent of pomegranate fruit dry rot. This fungal pathogen is also well-known as responsible for both plant collar rot and leaf spot. Because of its aggressiveness and the worldwide diffusion of pomegranate crops, the selection of cultivars less susceptible to this pathogen might represent an interesting preventive control measure. In the present investigation, the role of polyphenols in the susceptibility to P. granati of the two royalties-free pomegranate cultivars Wonderful and Mollar de Elche was compared. Pomegranate fruit were artificially inoculated and lesion diameters were monitored. Furthermore, pathogen DNA was quantified at 12-72 h post-inoculation within fruit rind by a real time PCR assay setup herein, and host total RNA was used in expression assays of genes involved in host-pathogen interaction. Similarly, protein extracts were employed to assess the specific activity of enzymes implicated in defense mechanisms. Pomegranate phenolic compounds were evaluated by HPLC-ESI-MS and MS2. All these data highlighted 'Wonderful' as less susceptible to P. granati than 'Mollar de Elche'. In the first cultivar, the fungal growth seemed controlled by the activation of the phenylpropanoid pathway, the production of ROS, and the alteration of fungal cell wall. Furthermore, antifungal compounds seemed to accumulate in 'Wonderful' fruit following inoculation. These data suggest that pomegranate polyphenols have a protective effect against P. granati infection and their content might represent a relevant parameter in the selection of the most suitable cultivars to reduce the economic losses caused by this pathogen.


Assuntos
Resistência à Doença , Micromonosporaceae/crescimento & desenvolvimento , Doenças das Plantas/microbiologia , Polifenóis/metabolismo , Punica granatum , Frutas/metabolismo , Frutas/microbiologia , Punica granatum/metabolismo , Punica granatum/microbiologia
4.
Chembiochem ; 21(11): 1629-1632, 2020 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-31957947

RESUMO

Five new members of the salinilactone family, salinilactones D-H, are reported. These bicyclic lactones are produced by Salinispora bacteria and display extended or shortened alkyl side chains relative to the recently reported salinilactones A-C. They were identified by GC/MS, gas chromatographic retention index, and comparison with synthetic samples. We further investigated the occurrence of salinilactones across six newly proposed Salinispora species to gain insight into how compound production varies among taxa. The growth-inhibiting effect of this compound family on multiple biological systems including non-Salinispora actinomycetes was analyzed. Additionally, we found strong evidence for significant cytotoxicity of the title compounds.


Assuntos
Actinobacteria/química , Organismos Aquáticos/química , Produtos Biológicos/farmacologia , Lactonas/farmacologia , Micromonosporaceae/química , Actinobacteria/metabolismo , Actinoplanes/efeitos dos fármacos , Actinoplanes/crescimento & desenvolvimento , Organismos Aquáticos/metabolismo , Produtos Biológicos/química , Produtos Biológicos/classificação , Produtos Biológicos/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas , Lactonas/química , Lactonas/classificação , Lactonas/isolamento & purificação , Testes de Sensibilidade Microbiana , Micromonospora/efeitos dos fármacos , Micromonospora/crescimento & desenvolvimento , Micromonosporaceae/efeitos dos fármacos , Micromonosporaceae/crescimento & desenvolvimento , Micromonosporaceae/metabolismo , Estrutura Molecular
5.
Microbiology (Reading) ; 164(7): 946-955, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29877785

RESUMO

Bacterial genome sequences consistently contain many more biosynthetic gene clusters encoding specialized metabolites than predicted by the compounds discovered from the respective strains. One hypothesis invoked to explain the cryptic nature of these gene clusters is that standard laboratory conditions do not provide the environmental cues needed to trigger gene expression. A potential source of such cues is other members of the bacterial community, which are logical targets for competitive interactions. In this study, we examined the effects of such interactions on specialized metabolism in the marine actinomycete Salinispora tropica. The results show that antibiotic activities and the concentration of some small molecules increase in the presence of co-occurring bacterial strains relative to monocultures. Some increases in antibiotic activity could be linked to nutrient depletion by the competitor as opposed to the production of a chemical cue. Other increases were correlated with the production of specific compounds by S. tropica. In particular, one interaction with a Vibrio sp. consistently induced antibiotic activity and was associated with parent ions that were unique to this interaction, although the associated compound could not be identified. This study provides insight into the metabolomic complexities of bacterial interactions and baseline information for future genome mining efforts.


Assuntos
Interações Microbianas/fisiologia , Micromonosporaceae/metabolismo , Antibacterianos/metabolismo , Proteínas de Bactérias/metabolismo , Cromatografia Líquida de Alta Pressão , Técnicas de Cocultura , Metabolômica , Micromonosporaceae/crescimento & desenvolvimento , Espectrometria de Massas em Tandem
6.
J Bacteriol ; 199(12)2017 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-28348024

RESUMO

The rare actinomycete Actinoplanes missouriensis forms sporangia, including hundreds of flagellated spores that start swimming as zoospores after their release. Under conditions suitable for vegetative growth, zoospores stop swimming and germinate. A comparative proteome analysis between zoospores and germinating cells identified 15 proteins that were produced in larger amounts in germinating cells. They include an orthologue of BldD (herein named AmBldD [BldD of A. missouriensis]), which is a transcriptional regulator involved in morphological development and secondary metabolism in Streptomyces AmBldD was detected in mycelia during vegetative growth but was barely detected in mycelia during the sporangium-forming phase, in spite of the constant transcription of AmbldD throughout growth. An AmbldD mutant started to form sporangia much earlier than the wild-type strain, and the resulting sporangia were morphologically abnormal. Recombinant AmBldD bound a palindromic sequence, the AmBldD box, located upstream from AmbldD 3',5'-Cyclic di-GMP significantly enhanced the in vitro DNA-binding ability of AmBldD. A chromatin immunoprecipitation-sequencing analysis and an in silico search for AmBldD boxes revealed that AmBldD bound 346 genomic loci that contained the 19-bp inverted repeat 5'-NN(G/A)TNACN(C/G)N(G/C)NGTNA(C/T)NN-3' as the consensus AmBldD-binding sequence. The transcriptional analysis of 27 selected AmBldD target gene candidates indicated that AmBldD should repress 12 of the 27 genes, including bldM, ssgB, whiD, ddbA, and wblA orthologues. These genes are involved in morphological development in Streptomyces coelicolor A3(2). Thus, AmBldD is a global transcriptional regulator that seems to repress the transcription of tens of genes during vegetative growth, some of which are likely to be required for sporangium formation.IMPORTANCE The rare actinomycete Actinoplanes missouriensis undergoes complex morphological differentiation, including sporangium formation. However, almost no molecular biological studies have been conducted on this bacterium. BldD is a key global regulator involved in the morphological development of streptomycetes. BldD orthologues are highly conserved among sporulating actinomycetes, but no BldD orthologues, except one in Saccharopolyspora erythraea, have been studied outside the streptomycetes. Here, it was revealed that the BldD orthologue AmBldD is essential for normal developmental processes in A. missouriensis The AmBldD regulon seems to be different from the BldD regulon in Streptomyces coelicolor A3(2), but they share four genes that are involved in morphological differentiation in S. coelicolor A3(2).


Assuntos
Regulação Bacteriana da Expressão Gênica , Micromonosporaceae/crescimento & desenvolvimento , Micromonosporaceae/genética , Proteínas Repressoras/metabolismo , Esporângios/crescimento & desenvolvimento , Sítios de Ligação , DNA Bacteriano/metabolismo , Perfilação da Expressão Gênica , Ligação Proteica , Proteínas Repressoras/genética
7.
World J Microbiol Biotechnol ; 32(1): 3, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26712618

RESUMO

Many investigations have revealed that a certain concentration of osmolality was indispensable for efficient acarbose production, but little information was available on the response mechanism of acarbose-producing strains to osmotic stress. By using the gas chromatography-mass spectrometry (GC-MS) analysis coupled with the enzyme activity determination of central carbon metabolism, the present work investigated the metabolic characteristics of industrial acarbose-producing Actinoplanes sp. A56 under various osmolality levels. Relatively high osmolality (450-500 mOsm/kg) appeared to favor efficient acarbose production by Actinoplanes sp. A56, although it inhibited cell growth. Further GC-MS analysis showed that fatty acids were the uppermost differential intracellular metabolites under various osmolality levels, and the relatively high osmolality resulted in increases in levels of fatty acids.


Assuntos
Acarbose/metabolismo , Micromonosporaceae/metabolismo , Concentração Osmolar , Reatores Biológicos , Carbono/metabolismo , Ácidos Graxos/análise , Ácidos Graxos/metabolismo , Fermentação , Cromatografia Gasosa-Espectrometria de Massas/métodos , Glicólise , Concentração de Íons de Hidrogênio , Microbiologia Industrial , Maltose/metabolismo , Micromonosporaceae/crescimento & desenvolvimento , Família Multigênica , Pressão Osmótica , Oxigênio/metabolismo
8.
J Antibiot (Tokyo) ; 68(6): 379-84, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25605042

RESUMO

The actinomycete strain RY35-23(T) was isolated from peat swamp forest soil in Thailand. The taxonomic position of this strain was determined using polyphasic approach. Strain RY35-23(T) showed typical morphology and chemical properties similar to the members in the genus Dactylosporangium. On the basis of 16S ribosomal RNA gene analysis, this strain was closely related to Dactylosporangium fulvum JCM 5631(T) (98.94%), D. roseum JCM 3364(T) (98.87%) and D. darangshiense JCM 17441(T) (98.86%). The DNA-DNA relatedness between strain RY35-23(T) and its closely related species was lower than 70%, the cutoff level for assigning strains to the same species. On the basis of these results mentioned, the strain RY35-23(T) could be distinguished from its closely related type strains and represents a novel species of the genus Dactylosporangium, for which the name Dactylosporangium sucinum (type strain RY35-23(T)=JCM 19831(T)=TISTR 2212(T)=PCU 333(T)) is proposed.


Assuntos
Micromonosporaceae/isolamento & purificação , Microbiologia do Solo , Quimiotaxia , Metabolismo Energético , Florestas , Metabolismo dos Lipídeos , Micromonosporaceae/classificação , Micromonosporaceae/crescimento & desenvolvimento , Micromonosporaceae/fisiologia , Microscopia Eletrônica de Varredura , Tipagem Molecular , Filogenia , Esporângios/fisiologia , Esporângios/ultraestrutura , Terminologia como Assunto , Tailândia , Áreas Alagadas
9.
J Biotechnol ; 168(4): 367-72, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24161919

RESUMO

Actinoplanes teichomyceticus is the only known producer of the valuable glycopeptide antibiotic teicoplanin. Random mutagenesis and selection were extensively applied to teicoplanin producers, while the gene engineering methods were not used, because of the paucity of genetic tools for A. teichomyceticus. Particularly, availability of promoters of different strength that are functional in Actinoplanes would be very useful for overexpression of beneficial genes. Here we report the use of a glucuronidase reporter system (gusA) for studying transcriptional activity in A. teichomyceticus and describe the behavior of a set of heterologous promoters in this strain. We reveal several elements that exceed in their strength the well-established Streptomyces promoter ermEp, underscoring the utility of the gusA reporter for Actinoplanes sp. Remarkable overproduction of teicoplanin was achieved by constructing strains carrying additional copies of the regulatory gene tcp28 under the control of one of the two most active promoters, moeE5p and actp, discovered in this study.


Assuntos
Antibacterianos/biossíntese , Micromonosporaceae/genética , Regiões Promotoras Genéticas , Teicoplanina/biossíntese , Antibacterianos/metabolismo , Antibacterianos/uso terapêutico , Genes Reporter , Glucuronidase/genética , Micromonosporaceae/crescimento & desenvolvimento , Streptomyces/genética , Teicoplanina/metabolismo , Teicoplanina/uso terapêutico
10.
Biomed Res Int ; 2013: 705418, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23484146

RESUMO

Commercial production of acarbose is exclusively via done microbial fermentation with strains from the genera of Actinoplanes. The addition of C7N-aminocyclitols for enhanced production of acarbose and concurrently reduced formation of impurity C by cultivation of A. utahensis ZJB-08196 in 500-mL shake flasks was investigated, and validamine was found to be the most effective strategy. Under the optimal conditions of validamine addition, acarbose titer was increased from 3560 ± 128 mg/L to 4950 ± 156 mg/L, and impurity C concentration was concurrently decreased from 289 ± 24 mg/L to 107 ± 29 mg/L in batch fermentation after 168 h of cultivation. A further fed-batch experiment coupled with the addition of validamine (20 mg/L) in the fermentation medium prior to inoculation was designed to enhance the production of acarbose. When twice feedings of a mixture of 6 g/L glucose, 14 g/L maltose, and 9 g/L soybean flour were performed at 72 h and 96 h, acarbose titer reached 6606 ± 103 mg/L and impurity C concentration was only 212 ± 12 mg/L at 168 h of cultivation. Acarbose titer and proportion of acarbose/impurity C increased by 85.6% and 152.9% when compared with control experiments. This work demonstrates for the first time that validamine addition is a simple and effective strategy for increasing acarbose production and reducing impurity C formation.


Assuntos
Acarbose/metabolismo , Meios de Cultura/farmacologia , Inositol/análogos & derivados , Micromonosporaceae/crescimento & desenvolvimento , Meios de Cultura/química , Inositol/farmacologia
11.
Appl Microbiol Biotechnol ; 97(7): 3097-108, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23081774

RESUMO

The developmental cycle of the obligate marine antibiotic producer actinobacterium Salinispora arenicola isolated from a Great Barrier Reef marine sponge was investigated in relation to mycelium and spore ultrastructure, synthesis of rifamycin antibiotic compounds, and expression of genes correlated with spore formation and with rifamycin precursor synthesis. The developmental cycle of S. arenicola M413 on solid agar medium was characterized by substrate mycelium growth, change of colony color, and spore formation; spore formation occurred quite early in colony growth but development of black colonies occurred only at late stages, correlated with a change in spore maturity in relation to cell wall layers. Rifamycins were detected throughout the growth cycle, but changed in relative quantity at particular phases in the cycle, with a marked increase after 32 days. Expression of the spore division gene ssgA and the rifK gene for 3-amino-5-hydroxybenzoate synthase responsible for rifamycin precursor synthesis was seen even at early stages of the growth cycle. ssgA expression significantly increased between days 26 and 31, but rifK expression effectively remained constant throughout the growth cycle, consistent with the early synthesis of rifamycin. Factors other than precursor synthesis may be responsible for an observed late increase in rifamycin production. A useful approach for measuring and exploring the regulation of antibiotic synthesis and gene expression in the marine natural product producer S. arenicola has been established.


Assuntos
Antibacterianos/metabolismo , Micromonosporaceae/crescimento & desenvolvimento , Micromonosporaceae/metabolismo , Poríferos/microbiologia , Rifamicinas/metabolismo , Animais , Proteínas de Bactérias/biossíntese , Proteínas de Bactérias/genética , Vias Biossintéticas/genética , Proteínas de Ciclo Celular/biossíntese , Proteínas de Ciclo Celular/genética , Meios de Cultura/química , Perfilação da Expressão Gênica , Micromonosporaceae/isolamento & purificação , Micromonosporaceae/ultraestrutura , Pigmentos Biológicos/metabolismo , Esporos Bacterianos/ultraestrutura , Fatores de Tempo
12.
J Microbiol Biotechnol ; 22(6): 826-31, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22573161

RESUMO

Acarbose, a pseudo-oligosaccharide, is widely used clinically in therapies for non-insulin-dependent diabetes. In the present study, S-adenosylmethionine (SAM) was added to selected media in order to investigate its effect on acarbose fermentation by Actinoplanes utahensis ZJB- 08196. Acarbose titer was seen to increase markedly when concentrations of SAM were added over a period of time. The effects of glucose and maltose on the production of acarbose were investigated in both batch and fed-batch fermentation. Optimal acarbose production was observed at relatively low glucose levels and high maltose levels. Based on these results, a further fed-batch experiment was designed so as to enhance the production of acarbose. Fed-batch fermentation was carried out at an initial glucose level of 10 g/l and an initial maltose level of 60 g/l. Then, 12 h post inoculation, 100 micromol/l SAM was added. In addition, 8 g/l of glucose was added every 24 h, and 20 g/l of maltose was added at 96 h. By way of this novel feeding strategy, the maximum titer of acarbose achieved was 6,113 mg/l at 192 h. To our knowledge, the production level of acarbose achieved in this study is the highest ever reported.


Assuntos
Acarbose/metabolismo , Micromonosporaceae/metabolismo , S-Adenosilmetionina/metabolismo , Biotecnologia/métodos , Meios de Cultura/química , Fermentação , Glucose/metabolismo , Maltose/metabolismo , Micromonosporaceae/crescimento & desenvolvimento
14.
Bioresour Technol ; 103(1): 337-42, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22029955

RESUMO

Acarbose, a potent α-glucosidase inhibitor, is as an oral anti-diabetic drug for treatment of the type two, noninsulin-dependent diabetes. Actinoplanes utahensis ZJB-08196, an osmosis-resistant actinomycete, had a broad osmolality optimum between 309 mOsm kg(-1) and 719 mOsm kg(-1). Utilizing this unique feature, an fed-batch culture process under preferential osmolality was constructed through intermittently feeding broths with feed medium consisting of 14.0 g l(-1) maltose, 6.0 g l(-1) glucose and 9.0 g l(-1) soybean meal, at 48 h, 72 h, 96 h and 120 h. This intermittent fed-batch culture produced a peak acarbose titer of 4878 mg l(-1), increased by 15.9% over the batch culture.


Assuntos
Acarbose/metabolismo , Técnicas de Cultura Celular por Lotes/métodos , Fermentação/fisiologia , Micromonosporaceae/fisiologia , Biomassa , Meios de Cultura/farmacologia , Fermentação/efeitos dos fármacos , Glucose/farmacologia , Maltose/farmacologia , Micromonosporaceae/efeitos dos fármacos , Micromonosporaceae/crescimento & desenvolvimento , Concentração Osmolar , Glutamato de Sódio/farmacologia , Fatores de Tempo
15.
Appl Microbiol Biotechnol ; 86(5): 1525-34, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20084507

RESUMO

In this paper, we report that three species of Salinispora, S. arenicola, S. tropica, and S. pacifica, require magnesium and calcium, for growth, with S. pacifica having the most stringent growth requirement for these ions. Interaction between these ions in supporting the growth of Salinispora was observed. We also demonstrated that the absolute requirement of sodium to support the growth of Salinispora has not been established as all three species of Salinispora can use either potassium or lithium to replace sodium to support maximum growth. While lithium can replace sodium to support maximum growth of Salinispora, it is more toxic to S. arenicola than S. tropica and S. pacifica, inhibiting the growth of S. arenicola at 189 mM but without effect on the growth of S. tropica and S. pacifica. Using both sodium chloride-based and lithium chloride-based media, we showed that Salinispora has a growth requirement for divalent ions, magnesium and calcium as well as growth requirement for ionic strength (8.29 to 15.2 mS/cm). S. arenicola has a lower growth requirement for ionic strength than S. tropica and S. pacifica.


Assuntos
Meios de Cultura/metabolismo , Micromonosporaceae/crescimento & desenvolvimento , Cátions Bivalentes/metabolismo , Cátions Monovalentes/metabolismo , Cloreto de Lítio/metabolismo , Magnésio/metabolismo , Micromonosporaceae/metabolismo , Concentração Osmolar , Cloreto de Potássio/metabolismo , Água do Mar , Cloreto de Sódio/metabolismo
16.
Int J Syst Evol Microbiol ; 60(Pt 6): 1256-1260, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19666791

RESUMO

A novel actinomycete was isolated from soil of a rock surface collected from the peak of Darangshi Oreum (Small Mountain) in Jeju, Republic of Korea. Phylogenetic analyses based on 16S rRNA gene sequences demonstrated that strain DLS-44(T) belonged to the genus Dactylosporangium, with the type strains of Dactylosporangium roseum (99.1 % sequence similarity) and Dactylosporangium fulvum (99.0 %) as the nearest phylogenetic relatives. Substrate mycelium was abundant, irregularly branched, twisted and vivid orange-yellow in colour. Aerial mycelium was not produced on most media tested. Finger-shaped sporangia and globose bodies were formed directly from the vegetative mycelium. The combination of morphological and chemotaxonomic characteristics supported assignment of the actinomycete to the genus Dactylosporangium. Strain DLS-44(T) could be distinguished clearly from all type strains of the genus based on its physiological properties (utilization of methyl alpha-d-mannoside and glycerol, nitrate reduction and growth at 20 degrees C and pH 9.1) and some chemotaxonomic characteristics (absence of unsaturated fatty acids). DNA-DNA relatedness values between strain DLS-44(T) and its closest phylogenetic relatives were 12.2-14.8 % with D. roseum DSM 43916(T) and 2.5-3.6 % with D. fulvum IMSNU 22055(T). On the basis of phenotypic, phylogenetic and DNA-DNA hybridization data, strain DLS-44(T) represents a novel species of the genus Dactylosporangium, for which the name Dactylosporangium darangshiense sp. nov. is proposed. The type strain is strain DLS-44(T) (=KCTC 19560(T) =DSM 45260(T)).


Assuntos
Micromonosporaceae/isolamento & purificação , Microbiologia do Solo , Algoritmos , Altitude , Técnicas de Tipagem Bacteriana , Meios de Cultura , DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , Ácidos Graxos/análise , Micromonosporaceae/classificação , Micromonosporaceae/crescimento & desenvolvimento , Dados de Sequência Molecular , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , República da Coreia
17.
Appl Microbiol Biotechnol ; 80(5): 873-80, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18677472

RESUMO

We recently described the development of a potassium-chloride-based salt formulation containing low sodium concentration (5.0 mM) to support the growth of Salinispora tropica strain NPS21184 and its production of salinosporamide A (NPI-0052). In order to determine whether the above low-sodium salt formulation can also support the growth of other S. tropica strains, we examined the growth of the type strain CNB440 and the parent strain CNB476, from which strain NPS21184 was derived as a single colony isolate. We demonstrated that good growth rate and yield of S. tropica strains CNB440 and CNB476, similar to S. tropica strain NPS21184 reported earlier, were detected in both agar and liquid media containing the potassium-chloride-based salt formulation with sodium concentration of 5.0 mM. Furthermore, we also detected good growth rate and yield of all three S. tropica strains on potassium-sulfate-based salt formulation agar medium containing both low-sodium (5.7 mM) and low-chloride (14 mM) content. This finding confirms the observation that the species of S. tropica does not have a seawater growth requirement but requirement for a specific combination of salts to provide a balance of salts and maintain a high enough ionic strength for growth.


Assuntos
Meios de Cultura/química , Meios de Cultura/metabolismo , Micromonosporaceae/crescimento & desenvolvimento , Micromonosporaceae/metabolismo , Água do Mar/microbiologia , Cloreto de Sódio/metabolismo , Lactonas , Micromonosporaceae/isolamento & purificação , Pirróis
18.
Appl Microbiol Biotechnol ; 78(5): 827-32, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18239915

RESUMO

Salinosporamide A (NPI-0052) is currently produced by a marine actinomycete, Salinispora tropica, via a saline fermentation process using a non-defined, commercially available synthetic sea salt, Instant Ocean. In order to control the consistency of the production of NPI-0052 and related analogs, two chemically defined salt formulations were developed to replace Instant Ocean. A chemically defined sodium-chloride-based salt formulation with similar sodium and chloride contents as in Instant Ocean was found to support higher production of NPI-0052 and a better metabolite production profile for downstream processing than Instant Ocean. A chemically defined sodium-sulfate-based salt formulation with low chloride concentration at 17 mM was found to support a similar NPI-0052 and metabolite production profile as Instant Ocean. The sodium-sulfate-based formulation is a robust formulation for large-scale production process due to its reduced corrosiveness in fermentation as compared with the saline fermentation utilizing Instant Ocean or the sodium-chloride-based salt formulation. The production of NPI-0052 in both chemically defined salt formulations was successfully scaled-up to a 42-l fermentor, indicating that these salt formulations can be used for large-scale manufacturing process.


Assuntos
Meios de Cultura/química , Lactonas/metabolismo , Micromonosporaceae/metabolismo , Pirróis/metabolismo , Cloreto de Sódio/metabolismo , Sedimentos Geológicos/microbiologia , Microbiologia Industrial , Lactonas/química , Espectrometria de Massas , Micromonosporaceae/crescimento & desenvolvimento , Pirróis/química , Cloreto de Sódio/análise
19.
Appl Microbiol Biotechnol ; 78(5): 821-6, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18239916

RESUMO

In this paper, we described the development of a potassium-chloride-based-salt formulation containing low sodium concentrations (5.0 to 11 mM) to support the growth of Salinispora tropica strain NPS21184 and its production of salinosporamide A (NPI-0052). The sodium present in the media was essentially derived from the complex nitrogen sources Hy Soy, yeast extract, and peptone used in the media. We demonstrated that good growth rate and yield of S. tropica strain NPS21184 were detected in both agar and liquid media containing the potassium-chloride-based-salt formulation with sodium concentration as low as 5.0 mM, significantly less than the critical seawater-growth requirement concentration of 50 mM sodium for a marine microorganism. We also observed good production of NPI-0052 (176 to 243 mg/l) by S. tropica strain NPS21184 grown in production media containing the potassium chloride-based-salt formulation. The production of deschloro analog, salinosporamide B (NPI-0047), was significantly lower in the low-sodium-salt-formulation medium than in the high-sodium-salt-formulation media. We demonstrated that while S. tropica strain NPS21184 is a novel marine actinomycete that requires high salt content for growth, it does not require sodium-chloride-based seawater-type media for growth and production of NPI-0052.


Assuntos
Meios de Cultura/química , Fermentação , Microbiologia Industrial , Lactonas/metabolismo , Micromonosporaceae/metabolismo , Pirróis/metabolismo , Compostos de Sódio/metabolismo , Lactamas/metabolismo , Micromonosporaceae/crescimento & desenvolvimento , Água do Mar/microbiologia
20.
Magn Reson Chem ; 46(1): 80-3, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18041008

RESUMO

A moderately thermophilic actinomycete strain, which was identified as Thermoactinomyces strain TA66-2, was isolated from hot-spring water. Fermentation, followed by solvent partition and chromatographic separations, resulted in the isolation of two new and two known molecules. The structures of the new compounds were elucidated as 2-(1-Propionylaminoethyl)thiazole-4-carboxylic acid [2-(1H-indol-3-yl)ethyl]amide and 2-(1-Acetylaminoethyl)thiazole-4-carboxylic acid [2-(1H-indol-3-yl)-ethyl]amide by using spectral methods (1D-, 2D-NMR and LC-ESI-MS).


Assuntos
Amidas/isolamento & purificação , Micromonosporaceae/química , Tiazóis/isolamento & purificação , Triptaminas/química , DNA Bacteriano/análise , Espectroscopia de Ressonância Magnética , Micromonosporaceae/genética , Micromonosporaceae/crescimento & desenvolvimento , Estrutura Molecular , Reação em Cadeia da Polimerase , Espectrometria de Massas por Ionização por Electrospray
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