南极菲尔德斯半岛土壤产酶细菌的鉴定及其系统发育分析

Identification and phylogenetic analysis of soil enzyme-producing bacteria from Fildes Peninsula,Antarctica

本研究针对菲尔德斯半岛10个不同微生态环境的土壤细菌,采用专用产酶平板培养法和16SrDNA测序法分别对分离菌的产胞外酶能力及系统发育进行了分析。结果显示:大多数产淀粉酶、蛋白酶、纤维素酶、酯类水解酶和藻胶酶等的菌株主要分布在离海岸较近、动植物比较丰富的区域,而半岛内陆产酶菌的数量与种类较少。在125株产胞外酶菌中发现有87株产酶能力较高,且许多株可产两种以上的酶;另外所有分离菌均不产明胶酶、卡拉胶酶和几丁质酶。64株产胞外酶能力较好代表菌的系统发育分析表明,它们共分布于7纲、17属;其中产淀粉酶菌株为3纲、5属,产蛋白酶菌株为7纲、14属,产纤维素酶菌株为1纲、1属,产酯类水解酶菌株为4纲、7属,产七叶苷酶菌株为7纲、13属,产DNA酶菌株为5纲、11属,产过氧化氢酶菌株为2纲、2属,产氧化酶菌株为1纲、1属。另外,还发现有6株菌可能为Pedobacter,Chryseobacterium,Flavobacterium和Kaistella属内的潜在新种。上述结果为研究开发低温微生物和适冷酶提供了有价值的参考和菌种源。

This study focuses on the soil bacteria isolated from 10 different micro-ecological environments on Fildes Peninsula.The extracellular enzyme producing capacity and species identification of the isolated bacteria were analyzed by special enzyme-producing plate culture and 16S rDNA sequencing methods,respectively.The results showed that most of the strains producing amylase,protease,cellulase,ester hydrolase and alginase were mainly distributed in the areas close to the coast and rich in animals ormosses,but relatively few species of extracellular enzyme producing bacteria were found in the inland of peninsula.Among 125 extracellular enzyme-producing bacteria,87 strains were found to have high extracellular enzyme-producing capacity,and many of them could produce more than two kinds of enzymes.In addition,none of the isolated bacteria produced gelatinase,carrageenase,or chitinase.Results of the phylogenetic analysis showed that the 64 representative strains with high extracellular enzyme producing capacity were in 7 classes,17 genera.Among them,the strains with high amylase producing capacity were in 3 classes,5 genera.Strains with high protease capacity were in 7 classes,14 genera.Strains with high cellulase capacity were in 1 class,1 genus,Strains with high ester hydrolase capacity were in 4 classes,7 genera,Strains with high a esculase capacity were in 7 classes,13 genera,Strains with high DNA hydrolase capacity were in 5 classes,11 genera.Strains with high catalase capacity were in 2 classes,2 genera.Strains with high oxidase capacity were in 1 class,1 genus.In addition,we also found that 6 strains could be the potential novel species in Pedobacter,Chryseobacterium,Flavobacterium,and Kaistella.This study provides valuable reference and strain resources for the research and development of cryogenic microorganisms and cryogenic enzymes.