Meiothermus rosaceus sp nov isolated from Tengchong hot spring in Yunnan, China

A rosy-pigmented Gram-negative, thermophilic bacterium with an optimum growth temperature of about 55degreesC was isolated from Tengchong hot springs in Yunnan province, China. Its growth scarcely occurred below 40degreesC or above 70degreesC. Phylogenetic and secondary structural analyses of 16S rRNA and DNA-DNA hybridization showed that the organism represented a new species of the genus Meiothermus. This new species could be distinguished easily from other species of the genus Meiothermus by the following phenotypic characteristics: rosy pigment, expanded body, sucrose and maltose were not utilized, gelatin and starch were not hydrolyzed. On the basis of the above data, the name Meiothermus rosaceus sp. nov. was proposed for the species represented by the strain RH9901(T)(CCTCC-AB200291). (C) 2002 Federation of European Microbiological Societies. Published by Elsevier Science B.V. All rights reserved.

Thermus rehai sp nov., isolated from Rehai of Tengchong, Yunnan Province, China

A yellow-pigmented strain of the genus Thermus, with optimum growth temperatures about 65-70 degreesC, was isolated from the hot springs in Rehai of Tengchong, Yunnan Province, China. Morphological, physiological and biochemical characteristics, pigment analysis of RH99-GF7504 strain and its phylogenetic analysis of 16S rDNA showed that this organism represented a new species of the genus Thermus(1)). This strain had maximum temperatures for growth below 80 degreesC. The new isolate from Rehai of Tengchong could be distinguished from other strains of the genus Thermus by its special structure and by its inability to hydrolyze gelatin and starch. On the basis of phylogenetic analysis, morphological, physiological and biochemical characteristics, the name Thermus rehai sp nov is proposed for the species, represented by strain RH99-GF7504 (CCTCC-AB200292).

Isolation and Characterization of a Methomyl-Degrading Paracoccus sp mdw-1

Methomyl, an extremely toxic pesticide, is widely used in agriculture. A strain named mdw-1 capable of degrading methomyl rapidly was successfully isolated from activated sludge in this study. It could utilize methomyl as the sole carbon or nitrogen source. The optimal temperature and medium pH for its growth and methomyl biodegradation were 30 degrees C and 7.0, respectively. It was identified as a Paracoccus sp. according to its morphological features, physiological and biochemical characteristics, and phylogenetic analysis based on the sequence of 16S rDNA. Gas chromatography-mass spectrometry (GC-MS) analysis showed that methomyl could be completely transformed to S-methyl-N-hydroxythioacetamidate in 10 h of incubation with the isolate mdw-1.

Rhodococcus qingshengii sp nov., a carbendazim-degrading bacterium

A Gram-positive, aerobic, non-motile, mesophilic strain, djl-6(T), able to degrade carbendazim, was isolated from a carbendazim-contaminated soil sample from Jiangsu province, China. The taxonomic position of this isolate was analysed by using a polyphasic approach. Chemotaxonomic analysis including peptidoglycan type, diagnostic sugar composition, fatty acid profile, menaquinones, polar lipids and mycolic acids showed that the characteristics of strain djl-6(T) were in good agreement with those of the genus Rhodococcus. DNA-DNA hybridization showed that it had low genomic relatedness with Rhodococcus baikonurensis DSM 44587(T) (31.8%), Rhodococcus erythropolis DSM 43066(T) (23.8%) and Rhodococcus globerulus DSM 43954(T) (117.7%), the three type strains to which strain djl-6(T) was most closely related based on 16S rRNA gene sequence analysis (99.78, 99.25 and 98.91% similarity, respectively). Based on the phenotypic properties and DNA-DNA hybridization data, strain djl-6(T) (=CGMCC 1.6580(T) =KCTC 19205(T)) is proposed as the type strain of a novel Rhodococcus species, Rhodococcus qingshengii sp. nov.

吸水链霉菌、放线菌Sp.253和金色毛壳菌的次生代谢产物研究

链霉菌是十分重要的一类放线菌，绝大多数的抗生素都由该类细菌产生。毛壳属真菌是一类重要的丝状真菌，从中也发现有很多结构新颖、活性独特的活性物质。因此本论文对两株链霉菌的活性成分及一株金毛壳菌的次生代谢产物进行了研究。 1．从吸水链霉菌（Streptomyces hygroscopicus 1.358）液态发酵产物（乙酸乙酯提取物）中分离得到3个化合物，通过波谱方法鉴定为RK955A (1)、Nigericin（2）、Elaiophylin（3）。以青霉素耐药-金黄色葡萄球菌作为指示菌的抗菌活性测定表明，三者均具有较强抗菌活性。 2．通过抗肿瘤体外活性筛选模型筛选得到得到一株链霉属土壤放线菌，从中分离得到六个化合物：苯乙酰胺（4）、苯丙酰胺（5）、肉桂酰胺（6）、3-（N-（甲酰胺基）乙酰基）吲哚（7）、鸟苷磷酸（8）、鸟苷（9）。 3．从金色毛壳菌（Chaetomium aureus）的固态培养物中分离得到13个化合物，利用波谱方法将其鉴定为：金毛壳菌素A（10）、金毛壳菌素B（11）、Eugenetin（12）、Eugenitol（13）、Chaetoquadrin A（14）、Chaetoquadrin B（15）、Chaetoquadrin G（16）、Chaetoquadrin H（17）、Chaetochromin A（18）、Sterigmatocystin（19）、O-methylsterigmatocystin（20）、3β-羟基-麦角甾-5，7，22-三烯（21）和过氧麦角甾醇（22）。 4．综述了聚醚类抗生素的结构、生物合成、生物活性及作用机理。 The genus Streptomyces (Actinomycetes) is an important group of microbe. Most antibiotics known nowdays are discovered from species of Streptomyces. The fungi of the genus Chaetomium have attracted much attention because various kinds of secondary metabolites with diverse bioactivities have been found from them. Thus, the bioactive compounds from two strains of Streptomyces and the secondary metabolites of Chaetomium aureus were investigated. 1. Three compounds were isolated from the ethyl acetate extract of the fermentation broth of Streptomyces hygroscopicus. They are identified to be elaiophylin (1), nigericin (2), and antibiotic RK955A (3) on the basis of their spectroscopic data. Compounds 1-3 possess antibacterial activities against Staphyloccocus aureus. 2. It was found that the extract of the fermented broth of a strain of Actinomycetes could inhibit some tumor cel lines. Separation of the bioactive fraction led to the isolation of six compounds. They were characterized to be phenylacetamide (4), phenylpropylamide (5), trans-cinnamamide (6), 3- (N- (formylmethyl) acetamide) indole (7), guanylicacid (8), and guanosine (9). 3. From the fermented broth of Chaetomium aureus, 13 compounds were isolated for the first time. They were determined to be chaetomiumycin A (10), chaetomiumycin B (11), eugenetin (12), eugenitol (13), chaetoquadrin A (14), chaetoquadrin B (15), chaetoquadrin G (16), chaetoquadrin H (17), chaetochromin A (18), sterigmatocystin (19), O-methylsterigmatocystin (20), 3β-hydroxyergosta-5, 7, 22-triene (21) and peroxy-ergosterol (22). Compounds 10 and 11 are new ones. 4. Structure, biosynthesis, biological activity, and mechanisms of polyether antibiotics were reviewed.

T-Muurolol Sesquiterpenes from the Marine Streptomyces sp M491 and Revision of the Configuration of Previously Reported Amorphanes

Two new sesquiterpenes, 15-hydroxy-T-muurolol (3d) and 11,15-dihydroxy-T-muurolol (3e), along with the plant cadinenes T-muurolol (3f) and 3 alpha-hydroxy-T-muurolol (3g), were isolated from the marine-derived Streptomyces sp. M491. Their absolute configuration was established via NMR spectroscopy and X-ray crystallography of 3-oxo-T-muurolol (3a), which was reisolated from this strain. In addition, the absolute configuration of further sesquiterpenes previously reported from this strain was revised. These products were tested for their cytotoxicity against 37 human tumor cell lines using the MTT method. Only 3d was cytotoxic against a range of human tumor cell lines with a mean IC50 of 6.7 mu g/mL.

Purification and characterization of the chitosanase from Aeromonas sp HG08

In this work, the characterization of a chitosanase-producing bacterium isolated from soil was reported and this strain was grouped under the genus Aeromonas by virtue of its morphological, physiological properties and 16S rDNA gene sequences. It is the first report that the genus Aeromonas could produce chitosanase. Aeromonas sp. HG08 could secrete the chitosanase ( named AsChi) with molecular weight of 70 kDa. The optimum pH and temperature of AsChi was 6.0 and 55 degrees C, respectively. The activity of AsChi was markedly enhanced by Mn2+ and inhibited by Fe3+, Cu2+, Ag+ and Hg2+; additionally, the activity of AsChi was increased with the degree of deacetylation ( DDA) of chitosan. Through viscosimetric assay, AsChi probably hydrolyzed chitosan in an endo-type fashion.

Isolation, antimicrobial activity, and metabolites of fungus Cladosporium sp associated with red alga Porphyra yezoensis

Cladosporium sp. isolate N5 was isolated as a dominant fungus from the healthy conchocelis of Porphyra yezoensis. In the re-infection test, it did not cause any pathogenic symptoms in the alga. Twenty-one cultural conditions were chosen to test its antimicrobial activity in order to obtain the best condition for large-scale fermentation. Phenylacetic acid, p-hydroxyphenylethyl alcohol, and L-beta-phenyllactic acid were isolated from the crude extract as strong antimicrobial compounds and they are the first reported secondary metabolites for the genus Cladosporium. In addition, the Cladosporium sp. produced the reported Porphyra yezoensis growth regulators phenylacetic acid and p-hydroxyphenylacetic acid. No cytotoxicity was found in the brine shrimp lethality test, which indicated that the environmental-friendly Cladosporium sp. could be used as a potential biocontrol agent to protect the alga from pathogens.

Heterologous expression and purification of recombinant allophycocyanin in marine Streptomyces sp isolate M097

Allophycocyanin is one of the most important marine active peptides. Previous studies suggested that recombinant allophycocyanin (rAPC) could remarkably inhibit the S-180 carcinoma in mice, indicating its potential pharmaceutical uses. Based on intergeneric conjugal transfer, heterologous expression of rAPC was first achieved in marine Streptomyces sp. isolate M097 through inserting the apc gene into the thiostrepton-induced vector pIJ8600. The transformation frequency for this system was approximately 10(-4) exconjugants/recipient. In the transformed Streptomyces sp. isolate M097, the yield of purified rAPC could amount to about 38 mg/l using a simple purification protocol, and HPLC analysis showed that the purity of the protein reached about 91.5%. In vitro activity tests also revealed that the purified rAPC had effective scavenging abilities on superoxide and hydroxyl radicals. This would widen the usefulness of the marine Streptomyces as a host to express the rAPC and to offer industrial strain for the production of rAPC.

attB site disruption in marine Actinomyces sp M048 via DNA transformation of a site-specific integration vector

An efficient conjugation method has been developed for the marine Actinomyces sp. isolate M048 to facilitate the genetic manipulation of the chandrananimycin biosynthesis gene cluster. A phi C31-derived integration vector pIJ8600 containing oriT and attP fragments was introduced into strain M048 by bi-parental conjugation from Escherichia coli ET12567 to strain M048. Transformation efficiency was (6.38 +/- 0.41) x 10(-5) exconjugants per recipient spore. Analysis of eight exconjugants showed that the plasmid pIJ8600 was stably integrated at a single chromosomal site (attB) of the Actinomyces genome. The DNA sequence of the attB was cloned and shown to be conserved. The results of antimicrobial activity analysis indicated that the insertion of plasmid pIJ8600 seemed to affect the biosynthesis of antibiotics that could strongly inhibit the growth of E. coli and Mucor miehei (Tu284). HPLC-MS analysis of the extracts indicated that disruption of the attB site resulted in the complete abolition of chandrananimycin A-C production, proving the identity of the gene cluster. Instead of chandrananimycins, two bafilomycins were produced through disruption of the attB site from the chromosomal DNA of marine Actinomyces sp. M048.

Wangia profunda gen. nov., sp nov., a novel marine bacterium of the family Flavobacteriaceae isolated from southern Okinawa Trough deep-sea sediment

An orange-pigmented, Gram-negative, nonmotile, strictly aerobic and oxidase- and catalase-positive bacterium (SM-A87(T)) was isolated from the deep-sea sediment of the southern Okinawa Trough area. The main fatty acids were i15 : 0, i17 : 0 3OH, i15 : 1 G, i17 : 1 omega 9c, 15 : 0, i15 : 0 3OH and summed feature 3 (comprising i-15 : 0 2OH and/or 16 : 1 omega 7c). MK-6 was the predominant respiratory quinone. DNA G+C content was 35.8 mol%. Flexirubin-type pigments were absent. Phylogenetic analyses based on 16S rRNA gene sequences revealed that strain SM-A87(T) formed a distinct lineage within the family Flavobacteriaceae, with < 93% sequence similarity to the nearest strain of genus Salegentibacter. Moreover, strain SM-A87(T) could be distinguished from the nearest phylogenetic neighbors by a number of chemotaxonomic and phenotypic properties. On the basis of polyphasic analyses, it is proposed that strain SM-A87(T) be classified in a novel genus and a new species in the family Flavobacteriaceae, designated Wangia profunda gen. nov., sp. nov. The type strain is SM-A87(T) (CCTCC AB 206139(T)=DSM 18752).

Myroides profundi sp nov., isolated from deep-sea sediment of the southern Okinawa Trough

A Gram-negative, nonmotile, aerobic and oxidase- and catalase-positive bacterium,, designated D25(T), was isolated from the deep-sea sediments of the southern Okinawa Trough area. Phylogenetic analyses of 16S rRNA gene sequences showed that strain D25(T), fell within the genus Myroides, with 99.2%, 96.0% and 93.4% sequence similarities to the only three recognized species of Myroides. However, the DNA-DNA similarity Value between strain D25(T) and its nearest neighbour Myroides odoratimimus JCM 7460(T) was only 49.9% ( < 70%). Several phenotypic properties could be used to distinguish strain D25(T) from other Myroides species. The main cellular fatty acids of strain D25(T) were iso-C-15:0, iso-C-17:1 omega 9C, iso-C(17:0)3-OH and Summed Feature 3 (comprising C-16:1 omega 7c and/or iso-C(15:0)2-OH). The major respiratory quinone was MK-6. The DNA G+C content was 33.0 mol%. The results of the polyphasic taxonomy analysis suggested that strain D251(T) represents a novel species of the genus Myroides, for which the name Myroides profundi sp. nov. is proposed. The type strain is D25(T) (=CCTCC M 208030(T) = DSM 19823(T)).

Diversity of Both the Cultivable Protease-Producing Bacteria and Their Extracellular Proteases in the Sediments of the South China Sea

Protease-producing bacteria are known to play an important role in degrading sedimentary particular organic nitrogen, and yet, their diversity and extracellular proteases remain largely unknown. In this paper, the diversity of the cultivable protease-producing bacteria and their extracellular proteases in the sediments of the South China Sea was investigated. The richness of the cultivable protease-producing bacteria reached 10(6) cells/g in all sediment samples. Analysis of the 16S rRNA gene sequences revealed that the predominant cultivated protease-producing bacteria are Gammaproteobacteria affiliated with the genera Pseudoalteromonas, Alteromonas, Marinobacter, Idiomarina, Halomonas, Vibrio, Shewanella, Pseudomonas, and Rheinheimera, with Alteromonas (34.6%) and Pseudoalteromonas (28.2%) as the predominant groups. Inhibitor analysis showed that nearly all the extracellular proteases from the bacteria are serine proteases or metalloproteases. Moreover, these proteases have different hydrolytic ability to different proteins, reflecting they may belong to different kinds of serine proteases or metalloproteases. To our knowledge, this study represents the first report of the diversity of bacterial proteases in deep-sea sediments.

Jiangella gansuensis gen. nov., sp nov., a novel actinomycete from a desert soil in north-west China

A novel actinomycete strain, designated YIM 002(T), was isolated from a desert soil sample in Gansu Province, north-west China. This actinomycete isolate formed well-differentiated aerial and substrate mycelia. In the early stages of growth, the substrate mycelia fragmented into short or elongated rods. Chemotaxonomically, it contained LL-2,6-diaminopimelic acid in the cell wall. The cell-wall sugars contained ribose and glucose. Phospholipids present were phosphatidylinositol mannosides, phosphatidylinositol and diphosphatidylglycerol. MK-9(H-4) was the predominant menaquinone. The major fatty acids were anteiso C-15:0 (35.92%), anteiso C-17:0 (15.84%), iso C-15:0 (10.40%), iso C-16:0 (7.07%) and C(17:10)w8c (9.37%). The G+C content of the DNA was 70 mol%. Phylogenetic analysis and signature nucleotide data based on 16S rRNA gene sequences showed that strain YIM 002(T) is distinct from all recognized genera of the family Nocardioidaceae in the suborder Propionibacterineae. On the basis of the phenotypic and genotypic characteristics, it is proposed that isolate YIM 002(T) be classified as a novel species in a new genus, Jiangella gansuensis gen. nov., sp. nov. The type strain is YIM 002(T) (= DSM 44835(T) = CCTCC AA 204001(T) = KCTC 19044(T)).

Pseudomonas aeruginosa vesicles associate with and are internalized by human lung epithelial cells.

BACKGROUND: Pseudomonas aeruginosa is the major pathogen associated with chronic and ultimately fatal lung infections in patients with cystic fibrosis (CF). To investigate how P. aeruginosa-derived vesicles may contribute to lung disease, we explored their ability to associate with human lung cells. RESULTS: Purified vesicles associated with lung cells and were internalized in a time- and dose-dependent manner. Vesicles from a CF isolate exhibited a 3- to 4-fold greater association with lung cells than vesicles from the lab strain PAO1. Vesicle internalization was temperature-dependent and was inhibited by hypertonic sucrose and cyclodextrins. Surface-bound vesicles rarely colocalized with clathrin. Internalized vesicles colocalized with the endoplasmic reticulum (ER) marker, TRAPalpha, as well as with ER-localized pools of cholera toxin and transferrin. CF isolates of P. aeruginosa abundantly secrete PaAP (PA2939), an aminopeptidase that associates with the surface of vesicles. Vesicles from a PaAP knockout strain exhibited a 40% decrease in cell association. Likewise, vesicles from PAO1 overexpressing PaAP displayed a significant increase in cell association. CONCLUSION: These data reveal that PaAP promotes the association of vesicles with lung cells. Taken together, these results suggest that P. aeruginosa vesicles can interact with and be internalized by lung epithelial cells and contribute to the inflammatory response during infection.