关中地区地下热泉普鲁兰酶产生菌的分离及其酶学性质

Isolation and Enzymatic Properties of Pullulanase Producing Strains from Hotsprings of Guanzhoug Region

摘要:

从关中地区的西安市区、临潼区、长安区, 以及杨凌周边地区, 分别采集地下热泉泉水水样, 采用培养法分别得到105株普鲁兰酶产生菌, 对其中21株进行16S rDNA基因片段序列分析。比对表明, 克雷伯菌属(Klebsiella)和芽孢杆菌属(Bacillus)在热泉生态系统中处于优势地位。根据统计结果, 所分离的菌株在种间和种内均有显著的酶活力差异。其中GP-1最适温度为50 ℃, 最适pH 4.0, 在50 ℃时有良好的稳定性, 保温30 min仍有92%剩余酶活。

Abstract:

The phylogenetic diversity of culturable pullulanase producing strains from hotsprings of guanzhong region, including Xi'an, Lintong District, Chang'an District and Yangling. A total of 105 pullulanase producing strains were isolated and 21 strains were analyzed. Analysis of 16S rDNA gene sequences revealed that Klebsiella and Bacillus is in the advantage position in the hot springs ecosystem. According to statistics, the isolated strains between species and within species showed a significant difference in enzyme activity. The optimal pH and temperature of GP-1 were 6.0 and 50 ℃ respectively. The enzyme showed stability at 65 ℃ after incubating for 30 min.