Sun Yumei, Ning Zhanguo, Yang Fan, Li Xianzhen
Pol J Microbiol. 2015;64(3):253-63.
An obligately thermophilic strain ZY-10 was isolated from the crude oil in a high-temperature oilfield, which was capable of degrading heavy crude oil. Phenotypic and phylogenetic analysis demonstrated that the isolate should be grouped in the genus Geobacillus, which shared thd highest similarity (99%) of the 16S rDNA sequence to Geobacillus stearothermophilus. However, the major cellular fatty acid iso-15:0 (28.55%), iso-16:0 (24.93%), iso-17:0 (23.53%) and the characteristics including indole production, tolerance to NaN3 and carbohydrate fermentation showed some difference from the recognized species in the genus Geobacillus. The isolate could use tridecane, hexadecane, octacosane and hexatridecane as sole carbon source for cell growth, and the digesting rate of long-chain alkane was lower than that of short-chain alkane. When the isolate was cultured in the heavy crude oil supplement with inorganic salts and trace yeast extract, the concentration of short-chain alkane was significantly increased and the content of long-chain alkane was decreased, suggesting that the larger hydrocarbon components in crude oil were degraded into shorter-chain alkane. Strain ZY-10 would be useful for improving the mobility of crude oil and upgrading heavy crude oil in situ.
从高温油田的原油中分离出一株嗜热专性菌株ZY-10，它能够降解重质原油。表型和系统发育分析表明，该分离株应归为嗜热栖热放线菌属，其16S rDNA序列与嗜热栖热放线菌的相似度最高（99%）。然而，主要细胞脂肪酸异-15:0（28.55%）、异-16:0（24.93%）、异-17:0（23.53%）以及包括吲哚产生、对NaN3的耐受性和碳水化合物发酵在内的特征与嗜热栖热放线菌属中已确认的物种存在一些差异。该分离株可以使用十三烷、十六烷、二十八烷和十三烷作为细胞生长的唯一碳源，长链烷烃的消化率低于短链烷烃。当该分离株在添加有无机盐和微量酵母提取物的重质原油中培养时，短链烷烃的浓度显著增加，长链烷烃的含量降低，这表明原油中较大的烃类成分被降解为较短链的烷烃。菌株ZY-10对于提高原油流动性和原位升级重质原油将是有用的。
