School of Biotechnology, Banaras Hindu University, Varanasi-221005, Uttar Pradesh, India.
J Microbiol Biotechnol. 2011 Nov;21(11):1101-8. doi: 10.4014/jmb.1106.06005.
The rise in global energy demand has prompted researches on developing strategies for transforming coal into a cleaner fuel. This requires isolation of microbes with the capability to degrade complex coal into simpler substrates to support methanogenesis in the coal beds. In this study, aerobic bacteria were isolated from an Indian coal bed that can solubilize and utilize coal as the sole source of carbon. The six bacterial isolates capable of growing on coal agar medium were identified on the basis of their 16S rRNA gene sequences, which clustered into two groups; Group I isolates belonged to the genus Rhizobium, whereas Group II isolates were identified as Chelatococcus species. Out of the 4 methods of whole genome fingerprinting (ERIC-PCR, REP-PCR, BOX-PCR, and RAPD), REPPCR showed maximum differentiation among strains within each group. Only Chelatococcus strains showed the ability to solubilize and utilize coal as the sole source of carbon. On the basis of 16S rRNA gene sequence and the ability to utilize different carbon sources, the Chelatococcus strains showed maximum similarity to C. daeguensis. This is the first report showing occurrence of Rhizobium and Chelatococcus strains in an Indian coal bed, and the ability of Chelatococcus isolates to solubilize and utilize coal as a sole source of carbon for their growth.
全球能源需求的增长促使人们研究开发将煤转化为更清洁燃料的策略。这需要分离出具有将复杂煤降解为更简单基质的能力的微生物，以支持煤层中的甲烷生成。在这项研究中，从印度一个煤层中分离出了好氧细菌，这些细菌能够将煤溶解并用作唯一的碳源。基于 16S rRNA 基因序列，从能够在煤琼脂培养基上生长的 6 个细菌分离株中鉴定出了 6 个细菌分离株，这些分离株聚类为两组；第 I 组分离株属于根瘤菌属，而第 II 组分离株被鉴定为 Chelatococcus 种。在 4 种全基因组指纹图谱（ERIC-PCR、REP-PCR、BOX-PCR 和 RAPD）方法中，REP-PCR 显示出每组菌株之间最大的差异。只有 Chelatococcus 菌株表现出溶解和利用煤作为唯一碳源的能力。基于 16S rRNA 基因序列和利用不同碳源的能力，Chelatococcus 菌株与 C. daeguensis 表现出最大的相似性。这是首次报道在印度煤层中出现根瘤菌和 Chelatococcus 菌株，以及 Chelatococcus 分离株溶解和利用煤作为唯一碳源来生长的能力。
