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ABSTRACT: To investigate the diversity of cultivable halophilic and halotolerant bacteria isolated from ordinary non-saline soil samples collected from Xiaoxi National Natural Reserve (28 degrees 42' 15"-28 degrees 53' 15" N, 110 degrees 6' 50"-110 degrees 21' 35" E), Hunan Province, China.
Bacterial strains were isolated from the samples by using the conventional culture-dependent method and investigated by using phylogenetic analysis based on 16S rRNA gene sequence comparisons.
We isolated 114 bacterial strains (8 moderately halophilic, 19 slightly halophilic, 87 halotolerant) from the samples on media (marine agar 2216, International Streptomyces Project medium 2 and 5, nutrient and humic acid agars) supplemented with 5% to 20% (w/v) NaCl. On the basis of morphological, physiological and biochemical characteristics, we selected 61 strains to perform a phylogenetic analysis based on 16S rRNA gene sequences. Results showed that 61 isolates represented 41 species, belonging to 18 genera (Actinomadura, Arthrobacter, Bacillus, Brachybacterium, Brevibacterium, Erwinia, Halobacillus, Jeotgalibacillus, Microbacterium, Microbulbifer, Nocardia, Pseudomonas, Rheinheimera, Rhodococcus, Sphingomonas, Staphylococcus, Streptomyces, Yaniella) of 16 families ( Alteromonadaceae, Bacillaceae, Brevibacteriaceae, Chromatiaceae, Dermabacteraceae, Enterobacteriaceae, Microbacteriaceae, Micrococcaceae, Nocardiaceae, Planococcaceae, Pseudomonadaceae, Sphingomonadaceae, Staphylococcaceae, Streptomycetaceae, Thermomonosporaceae, Yaniellaceae) in three phyla (Actinobacteria, Firmicutes, Proteobacteria). The most abundant and diverse isolates were within the phylum Firmicutes (38 strains; 62.3%) and the phylum Actinobacteria (18 strains; 29.5%). The phylogenetic distance matrix results suggested that there were obvious genetic divergences between most isolates and their closestly related type strains (16S rRNA gene sequence similarities ranged from 96.9% to 99.8%), and that, out of 61 isolates, at least 7 strains (JSM 070026, JSM 081004, JSM 081006, JSM 081008, JSM 083058, JSM 083085, JSM 084035) should represent 7 potential novel species within 6 characterized genera (Yaniella, Bacillus, Jeotgalibacillus, Sphingomonas, Rheinheimera, Microbulbifer).
The results presented here showed that there is abundant diversity of halophilic and halotolerant bacteria, as well as a number of novel species in non-saline soil collected from Xiaoxi National Natural Reserve, Hunan Province, China.
ACTA MICROBIOLOGICA SINICA 11/2010; 50(11):1452-9.
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ABSTRACT: To investigate the diversity of culturable bacteria isolated from the sea urchin Hemicentrotus pulcherrimus collected from a tidal flat of Naozhou Island (20 degrees 52'N - 20 degrees 56'N 110 degrees 33'E - 110 degrees 38'E), Leizhou Bay, South China Sea, China.
Bacteria were isolated from the sample by using conventional culture-dependent method and then investigated by using phylogenetic analysis based on 16S rRNA gene sequence comparisons.
We isolated 106 bacterial strains from the sample on media (Difco marine 2216, International Streotomyces Project medium 2, nutrient, sea water and humic acid agars) supplemented with 0 - 2 mol/L NaCl. On the basis of morphological, physiological and biochemical characteristics, we selected 34 strains to perform a phylogenetic analysis based on 16S rRNA gene sequences. Our results showed that 34 isolates represented 21 species, belonging to 17 genera (Alteromonas, Bacillus, Brachybacterium, Brevibacterium, Halobacillus, Halomonas, Nocardiopsis, Oceanobacillus, Piscibacillus, Planococcus, Pontibacillus, Pseudoalteromonas, Pseudonocardia, Salinicoccus, Salinivibrio, Staphylococcus, Vibrio, Virgibacillus) of 10 families (Alteromonadaceae, Bacillaceae, Brevibacteriaceae, Dermabacteraceae, Halomonadaceae, Planococcaceae, Pseudoalteromonadaceae, Pseudonocardiaceae, Nocardiopsaceae, Staphylococcaceae, Vibrionaceae) in three phylogenetic groups (Actinobacteria, Firmicutes, Gamma-Proteobacteria). The most abundant and diverse isolates were within the phylum Firmicutes (58.8%) and the subphylum Gamma-Proteobacteria (26.5%). The phylogenetic distance matrix results suggested that there were obvious genetic divergences between most isolates and their closestly related type strains (16S rRNA gene sequence similarities ranged from 99.6 to 99.9%), and that, out of 34 isolates, at least 5 strains (JSM 076033, JSM 076056, JSM 076093, JSM 078063, JSM 078169) could represent 5 potential new species within 5 characterized genera (Jeotgalicoccus, Pontibacillus, Halomonas, Bacillus, Sporosarcina), in which the descriptions of 3 novel species [Jeotgalicoccus marinus (type strain, JSM 076033), Pontibacillus halophilus (JSM 076056), Halomonas zhanjiangensis (JSM 078169)] have been published in IJSEM (International Journal of Systematic and Evolutionary Microbiology).
The results presented above showed that there are abundant bacteria diversity in the sea urchin Hemicentrotus pulcherrimus collected from Naozhou Island.
ACTA MICROBIOLOGICA SINICA 11/2009; 49(11):1424-9.
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ABSTRACT: To understand the diversity of cultivable bacteria isolated from a sea anemone collected from the coastal water of the Naozbou island in the Leizhou Bay on South China Sea.
Bacteria were isolated from a sea anemone by using conventional culture-dependent method and investigated by using phylogenetic analysis based on 165 rRNA gene sequence comparisons.
We isolated 126 bacteria strains from the sample on marine agar 2216 (Difco), International Streotomyces Project medium 2 agar, nutrient agar, sea water agar and humic acid agar supplemented with 0-2 mol/L NaCl. Based on partial morphological, physiological and biochemical characteristics, we selected 42 strains for molecular systematic study based on 16S rRNA gene sequences. Our results showed that 42 isolates were members of eighteen genera (Alteromonas, Bacillus, Brachybacterium, Brevibacterium, Halobacillus, Halomonas, Nocardiopsis, Oceanobacillus, Piscibacillus, Planococcus, Pontibacillus, Pseudoalteromonas, Pseudonocardia, Salinicoccus, Salinivibrio, Staphylococcus, Vibrio, Virgibacillus) of eleven families (Alteromonadaceae, Bacillaceae, Brevibacteriaceae, Dermabacteraceae, Halomonadaceae, Planococcaceae, Pseudoalteromonadaceae, Pseudonocardiaceae, Nocardiopsaceae, Staphylococcaceae, Vibrionaceae) in three major phylogenetic groups (Actinobacteria, Firmicutes, Gamma-Proteobacteria). The most abundant and diverse isolates were within the phylum Firmicutes (40.5%) and the subphylum Gamma-Proteobacteria (33.3%). The phylogenetic distance matrix results suggested that, out of 42 isolates, 37 were different strains of 19 known species,and that at least 6 strains represented 6 new species within 6 characterized genera.
The results presented above showed that there were abundant species diversity and phylogenetic diversity of bacteria isolated from the sea anemone.
ACTA MICROBIOLOGICA SINICA 03/2009; 49(2):246-50.
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ABSTRACT: To isolate new actinomycetes for discovering compounds of pharmaceutical importance.
We collected 280 soil samples from virgin forest in Wuling Mountain. In total 1134 actinomycetes were isolated by culture-dependent method. Of them 30 strains were selected and then characterized by phylogenetic analysis based on sequences of 16S rRNA gene. Antimicrobial activities were determined by agar well diffusion method, and genes of type I and II polyketide synthases (PKS I, PKS II), nonribosomal peptide synthase (NRPS) and polyene cytochrome P450 hydroxylase (CYP) were screened by PCR.
Thirty strains belonged to 8 families, 13 genera: Streptomyces (>70%), Micromonospora, Dactylosporangium, Catellatospora, Sphaerisporangium, Streptosporangium, Actinomadura, Nonomuraea, Nocardia, Rhodococcus, Arthrobacter, Microbacterium, and Pseudonocardia. There are 5 novel species candidates. Thirty strains showed different antimicrobial activities against one to three bacteria and pathogenic fungi.
Abundant diversity of actinomycetes existed in the virgin forest of Wuling Mountain which has many new taxa, and Streptomyces is the predominant population. The strains showed high antimicrobial activities and can be further researched for exploiting new compounds of pharmaceutical.
ACTA MICROBIOLOGICA SINICA 07/2008; 48(7):952-8.
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ABSTRACT: The spaA gene was amplified by PCR from the genomic DNA of Erysipelothrix rhusiopathiae C43311 strain, and inserted into the pMD18-T vector and then sequenced. The N-terminal protective domain of the spaA gene was amplified by PCR from the recombinant plasmid pMD18-spaA, then cloned into the prokaryotic expression vector pGEX-6p-2 and expressed in E. coli BL21 (DE3) by IPTG induction. The expressed protein was identified by SDS-PAGE and Western blot. The sequence analyses showed that the coding region of the spaA gene of C43311 strain was 1881bp in length, and the nucleotide sequence homology of the spaA genes between the C43311 strain and the previously reported different serotype strains of E. rhusiopathiae was 93 to 99%. The SDS-PAGE analyses revealed a single fusion protein band with a molecular weight of 64kDa, and the Western blot results showed that the GST-SpaA-N fusion protein was recognized specifically by an antiserum against the SpaA protein of C43311 strain, suggesting that the fusion protein of GST-SpaA-N possessed high immunoreactivity.
ACTA MICROBIOLOGICA SINICA 03/2008; 48(2):207-12.
