[Diversity of halophilic and halotolerant bacteria isolated from non-saline soil collected from Xiaoxi National Natural Reserve, Hunan Province].
OBJECTIVE
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.


METHODS
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.


RESULTS
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).


CONCLUSIONS
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.
College of Biology and Environment Sciences, Jishou University, Jishou 416000, China. chenqihui_808@163.com
Qihui
Q
Chen
Zhuxiang
Z
Liu
Qingzhong
Q
Peng
Ke
K
Huang
Jianwu
J
He
Li
L
Zhang
Wenjun
W
Li
Yiguang
Y
Chen
D001419:Bacteria / Q000145:classification / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D044822:Biodiversity; D002681:China; D004269:DNA, Bacterial / Q000235:genetics; D004275:DNA, Ribosomal / Q000235:genetics; D005618:Fresh Water / Q000382:microbiology; D019015:Geologic Sediments / Q000382:microbiology*; D008969:Molecular Sequence Data; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012965:Sodium Chloride / Q000378:metabolism*; D012988:Soil Microbiology
D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D012336:RNA, Ribosomal, 16S; D012965:Sodium Chloride