T he Role of the Overexpression of Suaeda maritima Choline Monooxygenase and Betaine Aldehyde Dehydrogenase cDNAs in the Enhancement of Salinity Tolerance in Different Strains of E.coli

Jordan Journal of Biological Sciences

Shrikanth Saraswathi Krishnamurthi¹ 

关键词: Salinity;    CMO;    BADH;    Glycine betaine;    Osmoprotectants;    E. coli.;   

DOI  :  

学科分类：生物科学（综合）

来源: Hashemite University, Deanship of Research and Higher Studies

【 摘 要 】

Heterologous expression of genes in to Escherichia coli helps establish the function of the encoded proteins in complex pathways of higher organisms. This methodology is particularly important in the case of plants where the whole genome sequence information is unavailable. Choline monooxygenase (CMO) and betaine aldehyde dehydrogenase (BADH) are two key enzymes of the glycine betaine biosynthetic pathway in Suaeda maritima, a halophyte found growing in the Pichavaram mangroves in Tamil Nadu. The present research is conducted to study the function of SmCMO and SmBADH cDNAs involved in glycine betaine biosynthetic pathway in Suaeda maritima in providing NaCl stress adaptability to E. coli. Three different E. coli strains namely DH5α, MC4100 and BL21 (DE3) are used for the study. Stability of pET32aSmCMO+pET32aSmBADH double recombinants and subsequent analyses for salinity tolerance in each of the strains were performed using pET32a protein expression vector. BL21 (DE3) double recombinants showed the maximum level of NaCl tolerance in both Minimal and LB media when compared with that of the other two strains as well as with non-recombinant BL21 (DE3) cells. This study enabled the functional characterization of S. maritima glycine betaine pathway genes as well as the additive effect of the cDNAs in conferring NaCl tolerance.

【 授权许可】

CC BY