一株耐酸产氢突变株Pantoea agglomerans的筛选与产氢特性

以红树林污泥中分离的厌氧发酵产氢细菌Pantoea agglomerans BH18为出发菌株,利用转座子Tn7随机插入菌株基因组DNA,通过卡那霉素筛选与PCR扩增验证,获得一批转座子插入突变菌株.起始pH4.0培养条件下,以产氢量为指标分离获得一株耐酸产氢突变菌株TB220.多次传代结果表明,突变菌株TB220具有稳定的产氢遗传特性.起始pH3.5~7.0范围内,突变菌株TB220最适产氢pH值为6.0,产氢量为(2.39±0.08)mol H2/mol葡萄糖.起始pH4.0和葡萄糖浓度10g/L的海水培养条件下,突变菌株TB220产氢量为(0.47 ± 0.02)mol H2/mol葡萄糖,比野生菌株高70%,表现出较强耐酸性.

Screening of an aciduric hydrogen producing mutant Pantoea agglomerans and characterization of hydrogen production.

A Tn7-based transposon was randomly inserted into genomic DNA of Pantoea agglomerans BH18,isolated from mangrove sludge.Mutants were screened by Kanr and amplification of the inserted sequences.At the initial pH 4.0,an aciduric and highly effective hydrogen producing mutant TB220 was screened using hydrogen production as screening index.The aciduric mutant TB220 was tested to have steady heredity and hydrogen-producing capability in several passages.The mutant TB220 was able to produce hydrogen over a wide rang of initial pH from 3.5 to 7.0,with an optimum initial pH of 6.0,and hydrogen production was(2.39 0.08)mol H2/mol glucose.Under the marine conditions with the initial pH of 4.0 and glucose concentration of 10 g/L,hydrogen production of the mutant TB220 was(0.47 0.02) mol H2/mol glucose,increasing by 70% compared with wild type.This indicated that the mutant showed high acid resistance capability.