Analysis of denitrifying bacteria in a long-term shell sand amended soil

Abstract:

[Objective] Analysis of the denitrifying bacteria composition in a long-term amended soil by pyrosequencing and isolating functional bacteria. [Methods] Microbial community structure was analyzed by 454 pyrosequencing of 16S rRNA gene, Giltay medium was used to cultivate and screen denitrifying bacteria from the isolates obtained from the soil, 16S rRNA genes of the detected denitrifying bacteria were also identified. [Results] Proteobacteria, Acidobacteria, Bacteroidetes, Chloroflexi were dominant in the soil sample and nearly 70% sequences were unclassified in genus level. Among 1 344 isolates, 12 isolates were found that could efficiently remove nitrate under anaerobic condition and were affiliated to Pseudomonas, Aeromonas, Serratia and Acinetobacter. [Conclusion] The results showed a high microbial diversity in the soil and most of them were unclassified bacteria. Eleven strains of denitrifying bacteria were identified via nitrate removal and gas formation. These strains could be used for studying the denitrification property.