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1.
Microorganisms ; 12(5)2024 Apr 25.
Article in English | MEDLINE | ID: mdl-38792687

ABSTRACT

Microbes naturally inhabit bamboo-based materials in outdoor environments, sequentially contributing to their deterioration. Fungi play a significant role in deterioration, especially in environments with abundant water and favorable temperatures. Alkali treatment is often employed in the pretreatment of round bamboo to change its natural elastic and aesthetic behaviors. However, little research has investigated the structure and dynamics of fungal communities on alkali-treated round bamboo during natural deterioration. In this work, high-throughput sequencing and multiple characterization methods were used to disclose the fungal community succession and characteristic alterations of alkali-treated round bamboo in both roofed and unroofed habitats throughout a 13-week deterioration period. In total, 192 fungal amplicon sequence variants (ASVs) from six phyla were identified. The fungal community richness of roofed bamboo samples declined, whereas that of unroofed bamboo samples increased during deterioration. The phyla Ascomycota and Basidiomycota exhibited dominance during the entire deterioration process in two distinct environments, and the relative abundance of them combined was more than 99%. A distinct shift in fungal communities from Basidiomycota dominant in the early stage to Ascomycota dominant in the late stage was observed, which may be attributed to the increase of moisture and temperature during succession and the effect of alkali treatment. Among all environmental factors, temperature contributed most to the variation in the fungal community. The surface of round bamboo underwent continuous destruction from fungi and environmental factors. The total amount of cell wall components in bamboo epidermis in both roofed and unroofed conditions presented a descending trend. The content of hemicellulose declined sharply by 8.3% and 11.1% under roofed and unroofed environments after 9 weeks of deterioration. In addition, the contact angle was reduced throughout the deterioration process in both roofed and unroofed samples, which might be attributed to wax layer removal and lignin degradation. This study provides theoretical support for the protection of round bamboo under natural weathering.

2.
Int J Biol Macromol ; 263(Pt 2): 130367, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38401588

ABSTRACT

The control of laccase-catalyzed efficiency often relies on the utilization of modifying enzyme molecules and shielding agents. However, their elevated costs or carcinogenicity led to the inability for large-scale application. To address this concern, we found that a low-cost protein from soybean meal can reduce lignin's ineffective adsorption onto enzymes for improving the efficiency of thymol grafting to lignosulfonate. The results demonstrated that by adding 0.5 mg/mL of additional soybean meal protein, the thymol reaction ratio of the modified lignosulfonate (L-0.5 S) significantly boosted from 18.1 % to 35.0 %, with the minimal inhibitory concentrations of the L-0.5 S against Aspergillus niger dramatically improved from 12.5 mg/mL to 3.1 mg/mL. Multiple characterization methods were employed to better understand the benefit of the modification under the addition of the soybean meal protein. The CO and R1-O group content increased from 20.5 % to 37.8 % and from 65.1 % to 75.5 %, respectively. The proposed potential reaction mechanism was further substantiated by the physicochemical properties. The incorporation of soybean meal effectively mitigated the non-specific adsorption of lignosulfonate, resulting in a reduction of the surface area of lignin from 235.0 to 139.2 m2/g. The utilization of soybean meal as a cost-effective and efficient shielding agent significantly enhanced the efficiency of subsequent enzyme catalysis. Consequently, the application of soybean meal in commercial enzyme catalysis holds considerable appeal and amplifies the relevance of this study in preservative industries.


Subject(s)
Lignin , Lignin/analogs & derivatives , Soybean Proteins , Lignin/chemistry , Laccase/metabolism , Thymol , Adsorption , Flour , Glycine max , Catalysis
3.
Polymers (Basel) ; 15(12)2023 Jun 09.
Article in English | MEDLINE | ID: mdl-37376283

ABSTRACT

The environmental moisture changes would result in the deformation and cracking of laminated bamboo lumber (LBL) easily due to the unreleased internal stress, leading to poor durability. In this study, a hydrophobic cross-linking polymer with low deformation was successfully fabricated and introduced in the LBL by polymerization and esterification to improve its dimensional stability. In an aqueous solution, the 2-hydroxyethyl methacrylate (HEMA) and Maleic anhydride (MAh) were employed as the base compounds for synthesizing the copolymer of 2-hydroxyethyl methacrylate and maleic acid (PHM). The hydrophobicity and swelling performance of the PHM was adjusted by controlling the reaction temperatures. PHM-modified LBL's hydrophobicity as indicated by the contact angle, increased from 58.5° to 115.2°. The anti-swelling efficiency was also improved. Moreover, multiple characterizations were applied to clarify the structure of PHM and its bonding linkages in LBL. This study demonstrates an efficient avenue to facilitate the dimensional stability of LBL by PHM modification and sheds new light on the efficient utilization of LBL using a hydrophobic polymer with low deformation.

4.
J Fungi (Basel) ; 9(6)2023 Jun 20.
Article in English | MEDLINE | ID: mdl-37367627

ABSTRACT

Bamboo's mechanical and aesthetic properties are significantly influenced by fungi. However, few studies have been conducted to investigate the structure and dynamics of fungal communities in bamboo during its natural deterioration. In this study, fungal community succession and characteristic variations of round bamboo in roofed and unroofed environments over a period of 13 weeks of deterioration were deciphered using high-throughput sequencing and multiple characterization methods. A total of 459 fungal Operational Taxonomic Units (OTUs) from eight phyla were identified. The fungal community's richness of roofed bamboo samples showed an increasing trend, whereas that of unroofed bamboo samples presented a declining trend during deterioration. Ascomycota and Basidiomycota were the dominant phyla throughout the deterioration process in two different environments: Basidiomycota was found to be an early colonizer of unroofed bamboo samples. Principal Coordinates Analysis (PCoA) analysis suggested that the deterioration time had a greater impact on fungal community variation compared to the exposure conditions. Redundancy analysis (RDA) further revealed that temperature was a major environmental factor that contributed to the variation in fungal communities. Additionally, the bamboo epidermis presented a descending total amount of cell wall components in both roofed and unroofed conditions. The correlation analysis between the fungal community and relative abundance of three major cell wall components elucidated that Cladosporium was negatively correlated with hemicellulose in roofed samples, whereas they presented a positive correlation with hemicellulose and a negative correlation with lignin in unroofed samples. Furthermore, the contact angle decreased during the deterioration process in the roofed as well as unroofed samples, which could arise from the degradation of lignin. Our findings provide novel insights into the fungal community succession on round bamboo during its natural deterioration and give useful information for round bamboo protection.

5.
R Soc Open Sci ; 9(11): 220247, 2022 Nov.
Article in English | MEDLINE | ID: mdl-36425518

ABSTRACT

Round bamboo has aroused much interest in construction for its mechanical properties, but poor biological durability seriously restricts its application. In order to develop a suitable and effective preservative treatment method for round bamboo, copper naphthenate (CuN) was adopted and impregnated into round bamboo using heat-cold procedure. The distribution and retention of copper naphthenate in round bamboo were studied, and the biological durability represented by the mould and decay resistance were investigated. The results showed that the retention and fixation of copper reached 0.39 kg⋅m-3 and 85.3%, respectively. Scanning electron microscopy-energy dispersive X-ray spectrometry further disclosed an increasing trend in the composition of CuN from the end inward. X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy analyses later revealed that CuN could be fixed on bamboo in the form of hydrogen bond or complex reaction. Statistical analysis showed that the increasing concentration of CuN from 0.3% to 0.5% and 0.8% (calculated as Cu2+ content) has significant contribution against Trametes versicolor and Gloeophyllum trabeum in comparison with the untreated bamboo. Meanwhile, when the concentration of treating solution increased to 0.8 wt%, the resisting efficacy for Aspergillus niger, Penicillium citrinum and Trichoderma viride soared as high as 85.9%, 94.8% and 70.3%, respectively.

6.
Int J Biol Macromol ; 217: 243-254, 2022 Sep 30.
Article in English | MEDLINE | ID: mdl-35835301

ABSTRACT

To improve the compatibility and reactivity of lignosulfonate (LS) with epoxy oligomers, the LS was firstly functionalized with anhydride via the carboxylation reaction. The carboxylated lignosulfonate (CLS) reinforced epoxy resin with excellent mechanical and shape memory performance was prepared facilely via distributing the CLS into the combined epoxy monomers of DGEBA and PEGDGE with the aid of water, rather than using the normal organic solvents. The incorporated CLS promoted the curing reaction of epoxy resin. A typical sea-island structure was formed in the cured sample at the CLS content of 5 phr, exhibiting the highest increases in tensile strength, modulus, elongation at break and toughness by 23.8 %, 18.2 %, 217 % and 113 %, respectively, relative to neat epoxy. Interestingly, the incorporation of CLS at a proper amount led to the simultaneous strengthening and toughing effects on cured epoxy resin, which could be attributed to the rigid structure of CLS covalently introduced in the epoxy resin network and the heterogeneous structure formed in the epoxy matrix. The rigid CLS component also restrained the movement of chain segments, consequently, the mechanical stability was enhanced and the fast shape recovery rate of epoxy resin network was slowed down to some extent.


Subject(s)
Epoxy Resins , Lignin , Carboxylic Acids , Epoxy Resins/chemistry , Lignin/analogs & derivatives , Lignin/chemistry , Solvents , Tensile Strength
7.
Polymers (Basel) ; 14(4)2022 Feb 14.
Article in English | MEDLINE | ID: mdl-35215651

ABSTRACT

The extension of wood to a wider field has been restrained significantly due to its dimensional instability that arises from variation in moisture content, which in turn brings about the risk of cracking, warping or distortion. This work proposed a novel strategy to stabilize wood by means of the in situ construction of a thermotropic shape memory polymer (SMP) inside wood. The cross-linked copolymer network (PMP) with good shape memory behavior was first investigated based on the reaction of methyl methacrylate (MMA) and polyethylene glycol diacrylate (PEGDA) in a water/ethanol solution; then, the PMP was constructed inside wood via vacuum-pressure impregnation and in situ polymerization. The weight gain, volume increment and morphology observations clearly revealed that the PMP was mainly present in wood cell lumens, cell walls and pits. The presence of PMP significantly enhanced the dimensional stability of and reduced the cracks in wood. The desirable shape recovery abilities of PMP under heating-cooling cycles were considered to be the main reasons for wood dimensional stabilization, because it could counteract the internal stress or retard the shrinkage of cell walls once water was evaporated from the wood. This study provided a novel and reliable approach for wood modification.

8.
Mol Biol Evol ; 39(1)2022 01 07.
Article in English | MEDLINE | ID: mdl-34626117

ABSTRACT

It is conventionally assumed that conserved pathways evolve slowly with little participation of gene evolution. Nevertheless, it has been recently observed that young genes can take over fundamental functions in essential biological processes, for example, development and reproduction. It is unclear how newly duplicated genes are integrated into ancestral networks and reshape the conserved pathways of important functions. Here, we investigated origination and function of two autosomal genes that evolved recently in Drosophila: Poseidon and Zeus, which were created by RNA-based duplications from the X-linked CAF40, a subunit of the conserved CCR4-NOT deadenylase complex involved in posttranscriptional and translational regulation. Knockdown and knockout assays show that the two genes quickly evolved critically important functions in viability and male fertility. Moreover, our transcriptome analysis demonstrates that the three genes have a broad and distinct effect in the expression of hundreds of genes, with almost half of the differentially expressed genes being perturbed exclusively by one paralog, but not the others. Co-immunoprecipitation and tethering assays show that the CAF40 paralog Poseidon maintains the ability to interact with the CCR4-NOT deadenylase complex and might act in posttranscriptional mRNA regulation. The rapid gene evolution in the ancient posttranscriptional and translational regulatory system may be driven by evolution of sex chromosomes to compensate for the meiotic X chromosomal inactivation (MXCI) in Drosophila.


Subject(s)
Drosophila Proteins , X Chromosome Inactivation , Animals , Drosophila/genetics , Drosophila/metabolism , Drosophila Proteins/genetics , Drosophila Proteins/metabolism , Evolution, Molecular , Genes, X-Linked , Male
9.
Int J Syst Evol Microbiol ; 70(11): 5861-5867, 2020 Nov.
Article in English | MEDLINE | ID: mdl-33044149

ABSTRACT

A novel, Gram-stain-positive, aerobic, non-spore-forming, non-motile and irregular rod-shaped bacterium designated Q22T was isolated from the rhizosphere soil of mangrove plant, Kandelia candel collected in Zhangzhou, Fujian province, China. Strain Q22T was able to grow at 10-40 °C (optimum 30 °C), pH 5.5-9.0 (optimum 7.0-8.0) and with 0-5.0% (w/v) NaCl (optimum 1.0 %). The genomic DNA G+C content was 71.9%. The average nucleotide identity, and in silico DNA-DNA hybridization values between strain Q22T and the reference strains were 79.7-88.9% and 22.6-37.4%, respectively. The predominant isoprenoid quinone was MK-12 and the major fatty acids were anteiso-C15:0, iso-C16:0 and anteiso-C17:0. The major polar lipids of strain Q22T were diphosphatidylglycerol, phosphatidylglycerol, one glycolipid and three unidentified lipids. The strain Q22T contained 2,4-diaminobutyric acid, alanine acid, glutamic acid and glycine in the peptidoglycans. The phylogenetic analysis and genotypic features, along with the phenotypic and chemotaxonomic characteristics, indicate that strain Q22T represents a novel species of the genus Agromyces, for which the name Agromyces kandeliae sp. nov. is proposed. The type strain is Q22T (=MCCC 1K03340T= KCTC 39961T).


Subject(s)
Actinobacteria/classification , Phylogeny , Rhizophoraceae/microbiology , Rhizosphere , Soil Microbiology , Actinobacteria/isolation & purification , Bacterial Typing Techniques , Base Composition , China , DNA, Bacterial/genetics , Fatty Acids/chemistry , Nucleic Acid Hybridization , Peptidoglycan/chemistry , Phospholipids/chemistry , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA , Vitamin K 2/chemistry
10.
Molecules ; 25(2)2020 Jan 17.
Article in English | MEDLINE | ID: mdl-31963465

ABSTRACT

Hf(OTf)4 was identified as a highly potent catalyst (0.1-0.5 mol%) for three-component Mannich reaction under solvent-free conditions. Hf(OTf)4-catalyzed Mannich reaction exhibited excellent regioselectivity and diastereoselectivity when alkyl ketones were employed as substrates. 1H NMR tracing of the H/D exchange reaction of ketones in MeOH-d4 indicated that Hf(OTf)4 could significantly promote the keto-enol tautomerization, thereby contributing to the acceleration of reaction rate.


Subject(s)
Hafnium/chemistry , Ketones/chemistry , Mesylates/chemistry , Catalysis , Mannich Bases/chemistry , Molecular Structure , Proton Magnetic Resonance Spectroscopy , Solvents
11.
Antonie Van Leeuwenhoek ; 113(3): 447, 2020 03.
Article in English | MEDLINE | ID: mdl-31916135

ABSTRACT

In the original publication of the article, the deposit accession numbers of strain 15181T in the acknowledgment section were incorrectly provided as "KCTC 62172T and MCCC 1K03442T".

12.
Int J Syst Evol Microbiol ; 69(6): 1669-1675, 2019 Jun.
Article in English | MEDLINE | ID: mdl-30942687

ABSTRACT

A Gram-stain-negative, aerobic, non-pigmented and short-rod-shaped bacterium, designated 34079T, was isolated from a water sample of a soda lake in Jilin, a province of China. Strain 34079T grew at 10-50 °C (optimum, 35 °C), pH 7-10 (optimum, pH 8.0-8.5). NaCl was required for growth at the concentration range 1-10.0 % (w/v), with an optimum at 2.5-4 % (w/v). Chemotaxonomic analysis indicated that the sole respiratory quinone was Q-10. The predominant cellular fatty acids (>5 %) were summed feature 8 (C18 : 1 ω7c/C18 : 1 ω6c) and C16 : 0. The major polar lipids consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine, three unidentified amino lipids, one unidentified amino phosphoglycolipid, one phosphoglycolipid, one unidentified glycolipid, three unidentified phospholipids and two unidentified lipids. The DNA G+C content was 65.6 mol%. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain 34079T formed a distinct lineage in the clade of the family 'Rhodobacteraceae' with the highest sequence similarity of 96.1 % to Pararhodobacter aggregans, followed by Rhodobaca bogoriensis DSM 18756T (95.7 %) and Roseibaca ekhonensis DSM 11469T (94.7 %). The distinct biochemical, chemotaxonomic and phylogenetic differences from the previously described taxa supported that strain 34079T represents a novel species of a new genus, for which the name Alkalilacustris brevis gen. nov., sp. nov. is proposed. The type strain is 34079T (=KCTC 62428T=MCCC 1K03493T).


Subject(s)
Lakes/microbiology , Phylogeny , Rhodobacteraceae/classification , Alkalies , Bacterial Typing Techniques , Base Composition , China , DNA, Bacterial/genetics , Fatty Acids/chemistry , Glycolipids/chemistry , Lakes/chemistry , Phospholipids/chemistry , RNA, Ribosomal, 16S/genetics , Rhodobacteraceae/isolation & purification , Sequence Analysis, DNA , Ubiquinone/analogs & derivatives , Ubiquinone/chemistry
13.
Int J Syst Evol Microbiol ; 69(6): 1662-1668, 2019 Jun.
Article in English | MEDLINE | ID: mdl-30942686

ABSTRACT

A Gram-staining negative, aerobic, motile and rod-shaped bacterium, designated ZQ330T, was isolated from rhizosphere soil of a mangrove (Avicennia marina) forest of Zhangzhou, Fujian Province, China. The growth range of NaCl concentration was 0.5-10.0 % (w/v), with an optimum at 2.5-3.0 % (w/v), the temperature range for growth was 10-40 °C, with an optimum at 28-30 °C, the pH range for growth was pH 6.0-9.5, with an optimum at pH 7.5. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain ZQ330T exhibited less than 97.0 % sequence similarity to all type strains with validly published names and revealed that strain ZQ330T formed a distinct lineage in the genus Idiomarina. The average nucleotide identity, and in silico DNA-DNA hybridization values between strain ZQ330T and the reference strains were 64.8-69.9 % and 27.5-28.4 %, respectively. Chemotaxonomic analysis indicated that the main respiratory quinone was Q-8, the predominant cellular fatty acids were iso-C15 : 0, iso-C17 : 0, summed feature 9 (C16 : 0 10-methyl and/or iso-C17 : 1ω9c), iso-C15 : 1F, C16 : 0, C18 : 0, summed feature 3 (C16 : 1ω8c and/or iso-C16 : 1 2-OH) and summed feature 8 (C18 : 1ω6c and/or C18 : 1ω7c). The polar lipid profile was composed of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, an unidentified glycolipid, an unidentified aminolipid, an unidentified phospholipid and two unidentified lipids. Based on the genotypic, phenotypic, chemotaxonomic and phylogenetic features, strain ZQ330T is considered to represent a novel species, for which the name Idiomarina mangrovi sp. nov. is proposed. The type strain is ZQ330T (=MCCC 1K03495T=KCTC 62455T).


Subject(s)
Avicennia/microbiology , Phylogeny , Rhizosphere , Soil Microbiology , Alteromonadaceae/genetics , Bacterial Typing Techniques , Base Composition , China , DNA, Bacterial/genetics , Fatty Acids/chemistry , Nucleic Acid Hybridization , Phospholipids/chemistry , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA , Ubiquinone/chemistry , Wetlands
14.
Molecules ; 24(4)2019 Feb 13.
Article in English | MEDLINE | ID: mdl-30781738

ABSTRACT

A P(V)-N activation method based on nucleoside phosphoropiperidate/DCI system has been developed for improved synthesis of diverse UDP-furanoses. The reaction conditions including temperature, amount of activator, and reaction time were optimized to alleviate the degradation of UDP-furanoses to cyclic phosphates. In addition, an efficient and facile phosphoramidite route was employed for the preparation of furanosyl-1-phosphates.


Subject(s)
Arabinose/analogs & derivatives , Imidazoles/chemistry , Imino Furanoses/chemical synthesis , Arabinose/chemical synthesis , Arabinose/chemistry , Imino Furanoses/chemistry , Nucleosides/chemistry , Phosphates/chemistry , Piperidines/chemistry , Uridine/chemistry
15.
Int J Syst Evol Microbiol ; 69(2): 377-383, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30601113

ABSTRACT

A Gram-stain-negative, aerobic, non-motile, short-rod-shaped bacterium, designated as strain TC11T, was isolated from rhizosphere soil of mangrove forest (Kandeliaobovata) in Fugong village, Zhangzhou, Fujian, China. Strain TC11T grew at 15-45 °C (optimum, 35 °C), 0-8 % (w/v) NaCl (optimum, 1 %, w/v) and pH 5.5-9.5 (optimum, pH 7.5). Phylogenetic analyses revealed that strain TC11T belonged to a clade of the genus Pseudomonas and showed the highest sequence similarity of 98.4 % to Pseudomonas fluvialis ASS-1T, followed by Pseudomonas oleovorans subsp.oleovorans DSM 1045T (97.9 %), Pseudomonas indoloxydans JCM 14246T (97.7 %), Pseudomonas guguanensis JCM 18416T(97.6 %) and Pseudomonas alcaliphila JCM 10630T (97.5 %) on the basis of their 16S rRNA gene sequences. The DNA G+C content was 64.3 mol%. In silico DNA-DNA hybridization and average nucleotide identity values between strain TC11T and the reference strains were 19-22 % and 72-78 %, respectively. Studies based on the three housekeeping genes, rpoB, gyrB and rpoD, further confirmed that strain TC11T is a novel member of the genus Pseudomonas. The major fatty acids of strain TC11Twere C16 : 0, summed feature 8 (C18 : 1ω6c/C18 : 1ω7c) and summed feature 3 (C16 : 1ω7c/C16 : 1ω6c). The sole isoprenoid quinone was Q-9. The major polar lipids were phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol. Based on the phenotypic, chemotaxonomic and phylogenetic properties, strain TC11T represents a novel species of the genus Pseudomonas, for which the name Pseudomonasmangrovi sp. nov., is proposed. The type strain is TC11T (=KCTC 62159=MCCC 1K03499).


Subject(s)
Phylogeny , Pseudomonas/classification , Rhizophoraceae/microbiology , Soil Microbiology , Bacterial Typing Techniques , Base Composition , China , DNA, Bacterial/genetics , Fatty Acids/chemistry , Genes, Bacterial , Nucleic Acid Hybridization , Phospholipids/chemistry , Pseudomonas/isolation & purification , RNA, Ribosomal, 16S/genetics , Rhizosphere , Sequence Analysis, DNA , Vitamin K 2/analogs & derivatives , Vitamin K 2/chemistry
16.
Int J Syst Evol Microbiol ; 69(2): 504-510, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30605070

ABSTRACT

A Gram-stain negative, pink-pigmented, strictly aerobic, non-motile and coccoid-shaped bacterial strain, designated TG-679T, was isolated from a deep-sea water sample collected from the South China Sea. Cells of strain TG-679T were catalase- and oxidase-positive, lacked bacteriochlorophyll a and carotenoid. Strain TG-679T was found to grow at 10-40 °C (optimum, 28 °C), pH 5.5-10.0 (optimum, pH 7.5) and with 0.5-2.0 % (w/v) NaCl (optimum, 1.5 %). Chemotaxonomic analysis of strain TG-679T indicated that the sole respiratory quinone was Q-10, the predominant cellular fatty acid was C18 : 1ω7c, and the major polar lipids consisted of phosphatidylethanolamine, phosphatidylmonomethylethanolamine, phosphatidylglycerol, phosphatidylcholine, an unidentified phospholipid and two unidentified glycolipids. The genomic DNA G+C content of strain TG-679T was 65.9 mol%. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain TG-679T constituted a separated branch in the family Rhodobacteraceae. Differential phenotypic properties, together with phylogenetic distinctiveness, demonstrated that strain TG-679T is clearly distinct from any validly published genus. Based on polyphasic taxonomic characterization, strain TG-679T is considered to represent a novel species of a novel genus, for which the name Meridianimarinicoccus roseus gen. nov., sp. nov. is proposed. The type strain of the species is TG-679T (=KCTC 62454T=MCCC 1K03496T).


Subject(s)
Phylogeny , Rhodobacteraceae/classification , Seawater/microbiology , Bacterial Typing Techniques , Base Composition , China , DNA, Bacterial/genetics , Fatty Acids/chemistry , Glycolipids/chemistry , Phospholipids/chemistry , RNA, Ribosomal, 16S/genetics , Rhodobacteraceae/isolation & purification , Sequence Analysis, DNA , Ubiquinone/analogs & derivatives , Ubiquinone/chemistry
17.
Molecules ; 24(2)2019 Jan 21.
Article in English | MEDLINE | ID: mdl-30669606

ABSTRACT

In our studies on the catalytic activity of Group IVB transition metal Lewis acids, Hf(OTf)4 was identified as a highly potent catalyst for "one-pot, three-component" Biginelli reaction. More importantly, it was found that solvent-free conditions, in contrast to solvent-based conditions, could dramatically promote the Hf(OTf)4-catalyzed formation of 3,4-dihydro-pyrimidin-2-(1H)-ones. To provide a mechanistic explanation, we closely examined the catalytic effects of Hf(OTf)4 on all three potential reaction pathways in both "sequential bimolecular condensations" and "one-pot, three-component" manners. The experimental results showed that the synergistic effects of solvent-free conditions and Hf(OTf)4 catalysis not only drastically accelerate Biginelli reaction by enhancing the imine route and activating the enamine route but also avoid the formation of Knoevenagel adduct, which may lead to an undesired byproduct. In addition, ¹H-MMR tracing of the H-D exchange reaction of methyl acetoacetate in MeOH-d4 indicated that Hf(IV) cation may significantly accelerate ketone-enol tautomerization and activate the ß-ketone moiety, thereby contributing to the overall reaction rate.


Subject(s)
Hafnium/chemistry , Lewis Acids/chemistry , Metals/chemistry , Pyrimidinones/chemical synthesis , Solvents/chemistry , Catalysis , Chemistry Techniques, Synthetic , Molecular Structure , Pyrimidinones/chemistry
18.
Antonie Van Leeuwenhoek ; 112(6): 847-855, 2019 Jun.
Article in English | MEDLINE | ID: mdl-30569387

ABSTRACT

A Gram-stain negative, non-motile, strictly aerobic and rod-shaped bacterium, designated as 15181T, was isolated from a salt lake in Xinjiang Province, China. Strain 15181T was able to grow at 10-40 °C (optimum 37 °C), pH 6.0-8.5 (optimum 7.0) and with 1-14% NaCl (optimum 4%, w/v). According to phylogenetic analysis based on 16S rRNA gene sequences, strain 15181T was assigned to the genus Wenzhouxiangella with high 16S rRNA gene sequence similarity of 97.4% to Wenzhouxiangella sediminis XDB06T, followed by Wenzhouxiangella marina KCTC 42284T (95.9%). Strain 15181T exhibited ANI values of 80.0% and 72.0% to W. sediminis XDB06T and W. marina KCTC 42284T, respectively. The in silico DDH analysis revealed that strain 15181T shared 19.1% and 18.7% DNA relatedness with W. sediminis XDB06T and W. marina KCTC 42284T, respectively. Chemotaxonomic analysis showed that the sole respiratory quinone was ubiquinone-8, the major fatty acids included iso-C15:0, iso-C16:0 and summed feature 9 (C16:0 10-methyl and/or iso-C17:1ω9c). The major polar lipids included diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, two unidentified glycolipids, two unidentified phospholipids, two unidentified aminophospholipids and an unidentified lipid. On the basis of phenotypic, genotypic and chemotaxonomic characteristics presented in this study, strain 15181T is concluded to represent a novel species in the genus Wenzhouxiangella, for which the name Wenzhouxiangella salilacus sp. nov. is proposed. The type strain is 15181T (=KCTC 62172T=MCCC 1K03442T).


Subject(s)
Gammaproteobacteria/isolation & purification , Lakes/microbiology , Bacterial Typing Techniques , China , DNA, Bacterial/genetics , Fatty Acids/chemistry , Fatty Acids/metabolism , Gammaproteobacteria/classification , Gammaproteobacteria/genetics , Gammaproteobacteria/metabolism , Lakes/analysis , Phylogeny , RNA, Ribosomal, 16S/genetics , Sodium Chloride/analysis , Sodium Chloride/metabolism
19.
Curr Microbiol ; 75(11): 1447-1452, 2018 Nov.
Article in English | MEDLINE | ID: mdl-30128842

ABSTRACT

A Gram-stain-negative, rod-shaped, non-motile, bacterial isolate designated 3BT, was isolated from a saline lake, and subjected to a polyphasic taxonomic investigation. The phylogenetic analysis based on 16S rRNA gene sequence clearly showed an allocation to the genus Confluentibacter with similarity ranging from 95.1 to 98%. OrthoANI values between strain 3BT and related strains of Confluentibacter (< 90%) were lower than the threshold value of 95% ANI relatedness recommended for species demarcation. Strain 3BT grew at 4-35 °C and pH 6.0-8.0 (optimum, 28 °C and pH 6.5) and with 0-3% (w/v) NaCl (optimum, 0.5%). The predominant respiratory quinone was menaquinone-6 (MK-6) and the major fatty acids were iso-C15:0, iso-C15:1 G, iso-C15:0 3-OH, and iso-C17:0 3-OH. The polar lipid profile of strain 3BT comprised phosphatidylethanolamine, one unidentified aminolipid, one aminophospholipid, and three unidentified lipids (L1-3). The DNA G+C content was 33.1 mol%. On the basis of morphological, physiological, and chemotaxonomic characteristics, together with the results of phylogenetic analysis, strain 3BT is described as a novel species in genus Confluentibacter, for which the name Confluentibacter flavum sp. nov. (type strain 3BT = CGMCC115960T = KCTC52969T) is proposed.


Subject(s)
Flavobacteriaceae/isolation & purification , Lakes/microbiology , Sodium Chloride/analysis , Base Composition , DNA, Bacterial/genetics , Fatty Acids/chemistry , Fatty Acids/metabolism , Flavobacteriaceae/classification , Flavobacteriaceae/genetics , Flavobacteriaceae/metabolism , Lakes/chemistry , Phylogeny , RNA, Ribosomal, 16S/genetics , Sodium Chloride/metabolism
20.
Curr Microbiol ; 75(8): 1055-1061, 2018 Aug.
Article in English | MEDLINE | ID: mdl-29632975

ABSTRACT

A novel, Gram-stain-positive, microaerophilic to aerobic, non-endospore-forming, no-motile and rod-shaped bacterium designated Q14T was isolated from mangrove soil samples collected on chengmai, Hainan province, China. Strain Q14T was able to grow at 10-40 °C (optimum 30 °C), pH 5.5-10.0 (optimum 6.5-8.0) and with 0.5-6% (w/v) NaCl (optimum 1%). The genomic DNA G+C content was 70.1%. The chemotaxonomic analysis showed that the predominant isoprenoid quinone was MK-12 and the major fatty acids were anteiso-C15:0, iso-C17:0 and anteiso-C17:0. The major polar lipids of strain Q14T were diphosphatidylglycerol, phosphatidylglycerol and one glycolipid. The strain Q14T contained 2,4-diaminobutylic acid (A2bu), alanine acid, glutamic acid and glycine in the peptidoglycans. The phylogenetic analysis and DNA-DNA hybridization, along with the phenotypic and chemotaxonomic characteristics, indicate that strain Q14T as a novel species of the genus Agromyces, for which the name Agromyces mangrovi sp. nov. is proposed. The type strain is Q14T (= MCCC 1K03191T = KCTC 39814T).


Subject(s)
Actinobacteria , Soil Microbiology , Actinobacteria/classification , Actinobacteria/genetics , Actinobacteria/isolation & purification , Bacterial Typing Techniques , Base Composition , Base Sequence , China , DNA, Bacterial/genetics , Fatty Acids/analysis , Nucleic Acid Hybridization , Peptidoglycan/analysis , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA , Wetlands
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