원문정보
초록
영어
Victivallis vadense ATCC BAA-548 is an anaerobic, cellobiose-degrading bacterium isolated from a human fecal sample by combining enrichments in liquid and soft-agar basal media. From the whole genomic sequence of V. vadense, one candidate for agarase gene was identified. The gene product was composed of 1427-amino acids and its molecular weight was calculated as 159,733 Da from the deduced amino acid sequence. Because it has been annotated as a putative alpha-agarase, expression and characterization of the gene product was performed. First, anaerobic cultivation of V. vadense was performed and chromosomal DNA was
isolated from the cultivated cells. And then, the gene encoding the putative alpha-agarase was cloned based on PCR. The cloned gene was expressed in Streptomyces lividans host, but no agarase activity was detected even though strong ermE promoter was used. Thus, we
investigated production of agarase by using the overexpression vector pET28a and the OmpA signal peptide in E.coli. Therefore, comparison of expression systems and characterization of the expressed protein with those of original signal sequence will be presented. [This work was
supported by the 21C frontier Microbial Genomics and Application Center Program]