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1.
The polyene antibiotics, including nystatin, pimaricin, amphotericin, and candicidin, comprise a family of very valuable antifungal polyketide compounds, and they are typically produced by soil actinomycetes. Previously, using a polyene cytochrome P450 hydroxylase-specific genome screening strategy, Pseudonocardia autotrophica KCTC9441 was determined to contain genes potentially encoding polyene biosynthesis. Here, sequence information of an approximately 125.7-kb contiguous DNA region in five overlapping cosmids isolated from the P. autotrophica KCTC9441 genomic library revealed a total of 23 open reading frames, which are presumably involved in the biosynthesis of a nystatin-like compound tentatively named NPP. The deduced roles for six multi-modular polyketide synthase (PKS) catalytic domains were found to be highly homologous to those of previously identified nystatin biosynthetic genes. Low NPP productivity suggests that the functionally clustered NPP biosynthetic pathway genes are tightly regulated in P. autotrophica. Disruption of a NPP PKS gene completely abolished both NPP biosynthesis and antifungal activity against Candida albicans, suggesting that polyene-specific genome screening may constitute an efficient method for isolation of potentially valuable previously identified polyene genes and compounds from various rare actinomycetes widespread in nature.  相似文献   

2.
Five strains (LN12, LN14T, LN15T, LN16 and LN17T) representing three novel methylotrophic yeast species were isolated from the external surface of plant leaves by three-consecutive enrichments. On the basis of morphological, biochemical, physiological and chemotaxonomic characteristics, the sequence analysis of the D1/D2 domain of the large subunit (LSU) rRNA gene and the phylogenetic analysis, the five strains were assigned to be one novel Ogataea species and two novel Candida species. Three strains (LN12, LN14T and LN16) represent a single novel species of the genus Ogataea, for which the name Ogataea phyllophila sp. nov. is proposed. The type strain is LN14T (= BCC 42666T = NBRC 107780T = CBS 12095T). Strain LN15T was assigned to be Candida chumphonensis sp. nov. (type strain LN15T = BCC 42667T = NBRC 107781T = CBS 12096T). Strain LN17T represented another novel species of Candida that was named Candida mattranensis sp. nov. (type strain LN17T = BCC 42668T = NBRC 107782T = CBS 12097T).  相似文献   

3.
Two strains representing a single novel yeast species were isolated from a flower of Calycoopteris floribunda Lame (SK170T) and insect frass (ST-122) collected in Thailand. On the basis of morphological, biochemical, physiological and chemotaxonomic characteristics, and the sequence analysis of the D1/D2 domain of the large subunit rRNA gene and the internal transcribed spacer region, the two strains were assigned as a single novel Candida species in the Hyphopichia clade for which the name Candida wangnamkhiaoensis sp. nov. is proposed. The type strain is SK170T=BCC 39604T=NBRC 106724T=CBS 11695T).  相似文献   

4.
The polyene antibiotics, a category that includes nystatin, pimaricin, amphotericin, and candicidin, comprise a family of very promising antifungal polyketide compounds and are typically produced by soil actinomycetes. The biosynthetic gene clusters for these polyenes have been previously investigated, revealing the presence of highly similar cytochrome P450 hydroxylase (CYP) genes. Using polyene CYP-specific PCR screening with several actinomycete genomic DNAs, Pseudonocardia autotrophica was determined to contain a unique polyene-specific CYP gene. Genomic DNA library screening using the polyene-specific CYP gene probe identified a positive cosmid clone, which contained a DNA fragment of approximately 34.5 kb. The complete sequencing of this DNA fragment revealed a total of seven complete and two incomplete open reading frames, which were found to be highly similar, but still unique, when compared to previously known polyene biosynthetic genes. These results suggest that the polyene-specific screening approach may constitute an efficient method for the isolation of potentially valuable cryptic polyene biosynthetic gene clusters from various rare actinomycetes.  相似文献   

5.
Hu H  Lin HP  Xie Q  Li L  Xie XQ  Sun M  Hong K 《Antonie van Leeuwenhoek》2011,100(4):631-637
An actinomycete strain, which was designated 172115T, was isolated from mangrove soil in Shenzhen, China. Strain 172115T fell within the genus Streptomyces in the 16S rRNA gene tree and could be grouped into this genus based on its chemotaxonomic and morphological data. The strain shared the highest 16S rRNA gene sequence similarities with Streptomyces lanatus NBRC 12787T (AB184845) (98.29%) and Streptomyces lucensis NBRC 13056T (AB184280) (98.26%). The DNA–DNA hybridization values between strain 172115T and the two most closely related type strains were low enough to justify the assignment of the strain to a novel species. On the basis of these phenotypic, phylogenetic and chemotaxonomic characteristics, 172115T represents a novel species of the genus Streptomyces, for which, the name Streptomyces shenzhenensis sp. nov. is proposed for strain 172115T (=CCTCC AA 2011001T=DSM 42034T).  相似文献   

6.

Background  

Polyenes represent a major class of antifungal agents characterised by the presence of a series of conjugated double bonds in their planar hydroxylated macrolide ring structure. Despite their general interest, very little is known about the factors that modulate their biosynthesis. Among these factors, we have recently discovered a new inducing compound (PI-factor) in the pimaricin producer Streptomyces natalensis, which elicits polyene production in a manner characteristic of quorum sensing. Here, we describe the involvement of an amino-acid exporter from S. natalensis in modulating the expression of pimaricin biosynthetic genes via secretion of the quorum-sensing pimaricin-inducer PI-factor.  相似文献   

7.
In a taxonomic study of yeasts isolated from decaying plant materials submerged in water of mangrove forests in Thailand, three strains isolated from tree bark (EM33T), a fallen leaf (EM40T) and a detached branch (SM56T) were found to represent three novel yeast species. On the basis of morphological, biochemical, physiological and chemotaxonomic characteristics, the sequence analysis of the D1/D2 domain of the large subunit (LSU) rRNA gene, and the phylogenetic analysis, the three strains were assigned as three novel Candida species. They were named as Candida chanthaburiensis sp. nov. (type strain EM33T = BCC 23057T = NBRC 102176T = CBS 10926T), Candida kungkrabaensis sp. nov. (type strain EM40T = BCC 23060T = NBRC 102179T = CBS 10927T), and Candida suratensis sp. nov. (type strain SM56T = BCC 25961T = NBRC 103858T = CBS 10928T).  相似文献   

8.
[背景]激发子(elicitin)是卵菌(Oomycetes)疫霉和腐霉分泌的可诱发宿主产生免疫反应的小分子化合物.[目的]鉴定紫菜腐霉激发子基因家族,分析其结构特征和在感染宿主过程中可能的作用机制.[方法]运用同源比对法筛查紫菜腐霉NBRC33253基因组中激发子基因家族成员,利用生物信息学工具分析激发子家族的理化性...  相似文献   

9.

Background

Actinobacteria of the genus Nocardia usually live in soil or water and play saprophytic roles, but they also opportunistically infect the respiratory system, skin, and other organs of humans and animals. Primarily because of the clinical importance of the strains, some Nocardia genomes have been sequenced, and genome sequences have accumulated. Genome sizes of Nocardia strains are similar to those of Streptomyces strains, the producers of most antibiotics. In the present work, we compared secondary metabolite biosynthesis gene clusters of type-I polyketide synthase (PKS-I) and nonribosomal peptide synthetase (NRPS) among genomes of representative Nocardia species/strains based on domain organization and amino acid sequence homology.

Results

Draft genome sequences of Nocardia asteroides NBRC 15531T, Nocardia otitidiscaviarum IFM 11049, Nocardia brasiliensis NBRC 14402T, and N. brasiliensis IFM 10847 were read and compared with published complete genome sequences of Nocardia farcinica IFM 10152, Nocardia cyriacigeorgica GUH-2, and N. brasiliensis HUJEG-1. Genome sizes are as follows: N. farcinica, 6.0 Mb; N. cyriacigeorgica, 6.2 Mb; N. asteroides, 7.0 Mb; N. otitidiscaviarum, 7.8 Mb; and N. brasiliensis, 8.9 - 9.4 Mb. Predicted numbers of PKS-I, NRPS, and PKS-I/NRPS hybrid clusters ranged between 4–11, 7–13, and 1–6, respectively, depending on strains, and tended to increase with increasing genome size. Domain and module structures of representative or unique clusters are discussed in the text.

Conclusion

We conclude the following: 1) genomes of Nocardia strains carry as many PKS-I and NRPS gene clusters as those of Streptomyces strains, 2) the number of PKS-I and NRPS gene clusters in Nocardia strains varies substantially depending on species, and N. brasiliensis strains carry the largest numbers of clusters among the species studied, 3) the seven Nocardia strains studied in the present work have seven common PKS-I and/or NRPS clusters, some of whose products are yet to be studied, and 4) different N. brasiliensis strains have some different gene clusters of PKS-I/NRPS, although the rest of the clusters are common within the N. brasiliensis strains. Genome sequencing suggested that Nocardia strains are highly promising resources in the search of novel secondary metabolites.

Electronic supplementary material

The online version of this article (doi: 10.1186/1471-2164-15-323) contains supplementary material, which is available to authorized users.  相似文献   

10.
林麟  杜如冰  吴群  徐岩 《微生物学通报》2022,49(8):3279-3292
【背景】耐酸乳杆菌(Lactobacillus acetotolerans)是白酒发酵过程中的优势乳酸菌,对白酒发酵具有重要作用。L. acetotolerans G10是分离自芝麻香型白酒发酵酒醅的一株能够利用多种碳源的菌株。【目的】基于全基因组测序,解析菌株G10多碳源利用机制。【方法】通过三代测序平台Oxford Nanopore完成菌株G10全基因组测序,分别利用Circlator和Prodigal对测序数据进行组装和基因预测;通过细菌基因组分析工具(bacterial pan genome analysis tool,BPGA)进行泛基因组分析。【结果】G10能够利用22种糖类及糖类衍生物,其全基因组大小为1 627 828 bp,含有1 878个编码基因;基于Koyto Encyclopedia of Genes and Genomes (KEGG)数据库注释获得292个碳源代谢相关基因,基于Carbohydrate-Active Enzymes (CAZy)数据库注释获得44个CAZy家族的编码基因。与其他发酵食品来源的耐酸乳杆菌相比,G10基因组最小,但其总基因数量以及...  相似文献   

11.
Yoon  Jaewoo 《Annals of microbiology》2019,69(12):1301-1308
Purpose

A polyphasic analysis was performed on a novel bacterium, designated strain KMU-143T, which was isolated from seawater collected in the Republic of Korea.

Methods

A novel marine bacterium KMU-143T was analyzed and described using a polyphasic taxonomic method including 16S rRNA gene sequence analysis, DNA–DNA hybridization, and physiological, biochemical, and chemotaxonomic analyses.

Results

Strain KMU-143T was Gram-stain-negative, strictly aerobic, oval-shaped, non-motile, and chemoorganoheterotrophic. Phylogenetic analysis based on the 16S rRNA gene sequence demonstrated that the novel marine bacterium belongs to the family Rhodobacteraceae, of the class Alphaproteobacteria, and that it possessed the highest (97.1%) sequence similarity with Sulfitobacter pontiacus ChLG 10T and Sulfitobacter undariae W-BA2T. DNA–DNA relatedness values between strains KMU-143T, S. pontiacus JCM 21789T, and S. undariae KCTC 42200T were less than 70%. The major isoprenoid quinone of the novel isolate was ubiquinone-10 (Q-10) and the major (> 10%) cellular fatty acids were C16:0 and C18:1 ω7c. The genomic DNA G+C content of strain KMU-143T was 56.1 mol%. The polar lipid profile of the strain KMU-143T was found to consist of phosphatidylglycerol, diphosphatidylglycerol, phosphatidylcholine, an unidentified aminolipid, and two unidentified lipids.

Conclusion

Based on the discriminative phylogenetic position and combination of genotypic and phenotypic properties, the strain is considered to represent a new species of the genus Sulfitobacter for which the name Sulfitobacter salinus sp. nov. is proposed. The type strain of S. salinus sp. nov. is KMU-143T (= KCCM 90322T = NBRC 113459T).

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12.
Three strains (LM008T, LM068 and LM078T), representing two novel yeast species were isolated from the phylloplane of three plant species by an enrichment technique. On the basis of morphological, biochemical, physiological and chemotaxonomic characteristics, and the sequence analysis of the D1/D2 domain of the large subunit rRNA gene and the internal spacer region, the three strains were assigned as two novel Candida species. Strain LM008T was assigned to be Candida sirachaensis sp. nov. (type strain LM008T = BCC 47628T = NBRC 108605T CBS 12094T) in the Starmerella clade. Two strains (LM068 and LM078T) represent a single species in the Lodderomyces-Spathaspora clade for which the name Candida sakaeoensis sp. nov. is proposed with the type strain LM078T = BCC 47632T = NBRC 108895T = CBS 12318T.  相似文献   

13.
A Gram-negative, aerobic, rod shaped, non-spore-forming bacterial strain, designated Dae08T, was isolated from sediment of the stream near Daechung dam in South Korea, and was characterized in order to determine its taxonomic position, using a polyphasic approach. Comparative 16S rRNA gene sequence analysis showed that strain Dae08T belongs to the family Xanthomonadaceae of the Gammaproteobacteria, and is related to Lysobacter brunescens ATCC 29482T (97.3%). The phylogenetic distances from any other species with validly published names within the genus Lysobacter were greater than 3.7%. The G+C contents of the genomic DNA of strain Dae08T was 69.3 mol%. The detection of a quinone system with Q-8 as the predominant compound and a fatty acid profile with iso-C15:0, iso-C17:1, ω9c, iso-C17:0, iso-C16:0, and iso-C11:0 3-OH as the major acids supported the affiliation of strain Dae08T to the genus Lysobacter. DNA-DNA relatedness between strain Dae08T and its phylogenetically closest neighbour was 28%. On the basis of its phenotypic properties and phylogenetic distinctiveness, strain Dae08T (= KCTC 12600T) should be classified in the genus Lysobacter as the novel species, for which the name Lysobacter daecheongensis sp. nov. is proposed.  相似文献   

14.
A halotolerant bacterium, strain SMB34T, was isolated from a naphthalene-utilizing bacterial consortium obtained from primitive technogeneous soil (Verkhnekamsk salt deposit, Perm region, Russia) by enrichment procedure. The strain itself was unable to degrade naphthalene and grew at NaCl concentrations up to 11% (w/v). The 16S rRNA-based phylogenetic analysis showed that the strain belongs to the genus Thalassospira. The DNA-DNA hybridization values between SMB34T and the type strains of phylogeneti-cally closest species (T. xiamenensis, T. profundimaris and T. tepidiphila) did not exceed 50%. The novel strain could be distinguished from the above species by the cell motility, MALDI/TOF mass spectra of whole cells and a range of physiological and biochemical characteristics. SMB34T also considerably differs from the recently described species T. xianhensis, with the most striking differences in the DNA G + C content (53. ± 1.0 vs. 61.2 ± 1.0 mol %) and predominant ubiquinones (Q-10 vs. Q-9). The data obtained suggest strain SMB34T (=VKM B-2527T = NBRC 106175T), designated as the type strain, represents a novel species, named Thalassospira permensis sp. nov.  相似文献   

15.
A novel Gram-stain positive, spore-forming, aerobic actinomycete, designated strain NEAU-QTH3-11T, was isolated from muddy soil collected from a stream in Qitaihe, Heilongjiang Province, northeast China and characterised using a polyphasic approach. The 16S rRNA gene sequence analysis showed that strain NEAU-QTH3-11T belongs to the genus Streptomyces and is closely related to Streptomyces rhizosphaerihabitans NBRC 109807T (99.38%) and Streptomyces mirabilis JCM 4791T (99.03%). Phylogenetic analysis based on the 16S rRNA gene sequences indicated that the strain formed a cluster with S. rhizosphaerihabitans NBRC 109807T and Streptomyces siamensis NBRC 108799T (98.62%). The menaquinones were identified as MK-9(H8), MK-9(H6) and MK-9(H4). The phospholipid profile was found to consist of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol, an unidentified phospholipid and an unidentified lipid. The major fatty acids were identified as anteiso-C15:0, iso-C16:0, C16:0 and C15:0. However, multilocus sequence analysis based on five house-keeping genes (atpD, gyrB, rpoB, recA and trpB), low DNA-DNA hybridization results and some phenotypic, physiological and biochemical properties could differentiate the strain from its close relatives in the genus Streptomyces. Therefore, strain NEAU-QTH3-11T is considered to represent a novel species of the genus Streptomyces, for which the name Streptomyces lutosisoli sp. nov. is proposed, with NEAU-QTH3-11T (=DSM 42165T=CGMCC 4.7198T) as the type strain.  相似文献   

16.
A novel actinomycete, designated strain NEAU-ycm1T, was isolated from an edible Chinese black ant (Polyrhachis vicina Roger) and characterized with a polyphasic approach. The organism was found to have morphological and chemotaxonomic characteristics typical of streptomycetes. Phylogenetic analysis based on the almost complete 16S rRNA gene sequence show that the novel isolate belongs to the genus Streptomyces and forms a separate subclade. The closest phylogenetic relatives were identified as the type strains of Streptomyces intermedius NBRC 13049T (97.74 %), Streptomyces aureoverticillatus NRRL B-3326T (97.69 %), Streptomyces rutgersensis NBRC 12819T (97.68 %), Streptomyces gougerotii NBRC 3198T (97.68 %) and Streptomyces diastaticus subsp. diastaticus NBRC 3714T (97.68 %). Similarities to other type strains of the genus Streptomyces were lower than 97.55 %. A comparison between strain NEAU-ycm1T and the closest related Streptomyces type strains revealed that it is different from them in morphological, physiological and biochemical characteristics. Therefore, it is proposed that NEAU-ycm1T (=CGMCC 4.7094T = DSM 42102T) represents a novel species of the genus of Streptomyces, for which the name Streptomyces polyrhachii sp. nov. is proposed.  相似文献   

17.
A novel Gram-negative and rod-shaped bacterium, designated N8T, was isolated from tidal flat sediment. Phylogenetic analysis based on 16S rRNA gene sequences showed that N8T strain is associated with the family Phyllobacteriaceae: two uncultured clones (98.4 and 99.8% 16S rRNA gene sequence similarity) and the genus Mesorhizobium (≤97.0%). The novel strain formed a separate clade with uncultured clones in the phylogenetic tree based on 16S rRNA gene sequences. Cellular fatty acid profiles predominately comprised C18:1 ω7c and C19:0 cyclo ω8c. The major isoprenoid quinone is ubiquinone-10 and genomic DNA G+C content is 53.4 mol%. The polyphasic taxonomic study indicates that the novel strain N8T represents a novel species of the new genus in the family Phyllobacteriaceae, named Aliihoeflea aestuarii. The type strain is N8T (= KCTC 22052T= JCM 15118T= DSM 19536T).  相似文献   

18.
A novel actinobacterium, strain SK68, was isolated from the rhizosphere of peanut plant and its salinity stress alleviation ability was studied using tomato (Solanum lycopersicum cv. Micro-Tom) plants. Based on 16S rDNA based phylogenetic analysis, strain SK68 has been identified as a Streptomyces sp. Strain SK68 had branched substrate mycelium bearing smooth surfaced spores and the spore colour is brownish grey on ISP4 medium. It exhibited enzyme activities such as xylanase, cellulase, amylase, and pectinase and degraded hypoxanthine, casein, and L-tyrosine. The strain SK68 differed in its banding pattern in BOX-PCR and RAPD fingerprinting compared to the closely matching type strains Streptomyces erythrochromogenes NBRC 3304T (AB184746), S. flavotricini NBRC 12770T (AB184132), S. racemochromogenes NBRC 12906T (AB184235), and S. polychromogenes NBRC 13072T (NR041109). Strain SK68 was evaluated for its salinity stress-alleviating activity in tomato plants with 180 mmol/L NaCl under gnotobiotic condition. A significant increase in plant biomass was observed in strain SK68-inoculated tomato plants under salt stress compared to control and salt-stressed non-inoculated plants.  相似文献   

19.

A pink-coloured, salt- and alkali-tolerant planctomycetal strain (JC658T) with oval to pear-shaped, motile, aerobic, Gram-negative stained cells was isolated from a marine sponge, Pseudoceratina sp. Strain JC658T shares the highest 16S rRNA gene sequence identity with Maioricimonas rarisocia Mal4T (<?89.2%) in the family Planctomycetaceae. The genomic analysis of the new strain indicates its biotechnological potential for the production of various industrially important enzymes, notably sulfatases and carbohydrate-active enzymes (CAZymes), and also potential antimicrobial compounds. Several genes encoding restriction-modification (RM) and CRISPR-CAS systems are also present. NaCl is obligate for growth, of which strain JC658T can tolerate a concentration up to 6% (w/v). Optimum pH and temperature for growth are 8.0 (range 7.0–9.0) and 25 ºC (range 10–40 °C), respectively. The major respiratory quinone of strain JC658T is MK6. Major fatty acids are C16:1ω7c/C16:1ω6c, C18:0 and C16:0. Major polar lipids are phosphatidylcholine, phosphatidyl-dimethylethanolamine and phosphatidyl-monomethylethanolamine. The genomic size of strain JC658T is 7.36 Mb with a DNA G?+?C?content of 54.6 mol%. Based on phylogenetic, genomic (ANI, AAI, POCP, dDDH), chemotaxonomic, physiological and biochemical characteristics, we conclude that strain JC658T belongs to a novel genus and constitutes a novel species within the family Planctomycetaceae, for which we propose the name Thalassoroseus pseudoceratinae gen. nov., sp. nov. The novel species is represented by the type strain JC658T (=?KCTC 72881 T?=?NBRC 114371 T).

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20.
A novel actinomycete strain, designated YIM 45720T, was isolated from a Cephalotaxus fortunei rhizophere soil sample collected from Yunnan Province, southwest China. The strain formed well-differentiated aerial and substrate mycelia. Chemotaxonomically, it contained LL-diaminopimelic acid in the cell wall. The cell-wall sugars contained ribose, mannose, and galactose with traces of glucose and xylose. Phospholipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine and phosphatidylinositol. MK-9 (H8) was the predominant menaquinone. The major fatty acids (>10%) were iso-C16:0, iso-C15:1 and anteiso-C15:0. The G + C content of the DNA was 70 mol%. Phylogenetic analysis data based on 16S rRNA gene sequence showed that strain YIM 45720T formed a distinct branch with the type strain of Streptomyces scabrisporus JCM 11712T within the genus Streptomyces. On the basis of the phenotypic and genotypic characteristics, strain YIM 45720T (=DSM 41883T = CCTCC AA 206006T) is proposed as the type strain of a novel species, Streptomyces serianimatus sp. nov.  相似文献   

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