Distribution characteristics of Bacillus-like species of Xiaokong Mountain volcanic valley in Tengchong County, Yunnan Province

Abstract:

[Objective] The study was aimed to determine the distribution of Bacillus-like species in volcanic valley of Xiaokong Montain, Tengchong County, Yunnan Province. [Methods] On the basis of culturable method, we isolated Bacillus-like species from soil samples collected in shady-slope, sunny-slope and valley bottom of Xiaokong Mountain. Then the isolates were identified using the 16S rRNA gene and phylogenetic tree was constructed to explore the relation between isolates and related type species. The correlation between environmental factors and community of Bacillus-like species was analyzed by software Cano 5. [Results] We obtained 180 isolates from the soil samples, and identified them as 2 families, 6 genera, 34 species using 16S rRNA gene sequences, including genus Bacillus (11 species), Paenibacillus (13 species), Brevibacillus (3 species), Lysinibacillus (4 species), Psychrobacillus (1 species) and Viridibacillus (2 species). Among them, 7 strains had the lower 16S rRNA similarities with their closest type strain, below the species threshold valus 98.65%, indicating that they were potential novel Bacillus species. The dominant genera were Bacillus and Paenibaciilus, and dominant species were B. mycoides, B. toyonensis, B. cereus, L. xylanilyticus, P. alvei and V. arenosi. Among the Bacillus-like species, we got 16 species from sunny-slope, 29 species from shady-slope and 10 species from valley bottom. The diversity index was showed that the order of Shannon index was shady-slope > sunny-slope > valley bottom. We also found that the correlation between Bacillus-like species community structure, altitude and carbon source was negative, but with S and nitrogen source was positive. [Conclusion] There were rich Bacillus-like species in volcanic valley, Tengchong County, Yunnan Province, and some novel potential Bacillus-like species.

Key words:cultural Bacillus-like species;volcanic valley;diversity