Molecular analysis of functional domain and protein motif of endoglucanase gene in marine bacteria isolated from Eucheuma sp. and Sargassum sp.

Abstract

Marine bacteria which are symbionts with Eucheuma sp. and Sargassum sp. has the ability to convert seloluse into glucose. These processes are important during bioethanol production. Identification using PCR and 16S rRNA primers showed that the symbiotic bacteria in Eucheuma sp. was B. subtilis (97% identical to accession number NR. 027552.1) and symbiotic bacteria in Sargassum sp. was B. thuringiensis (97% identical to access number NR. 043403.1). Cellulotic indexes were identified for B. subtilis (2.477 mm) and B. thuringiensis (6.102 mm). Amplification of the endoglucanase gene were conducted with Bac-EuF and Bac-EuR primers in B. subtilis with size at 1416 bp (95% identical to accession number WP_017696508.1), whereas in B. thuriengeinsis the size was 1251 bp (92% identical to the accession number EEM47662). In silico analysis of the endoglucanase gene, showed that the catalytic and cellulose binding domains of B. subtilis were GH5 (aa residue 1-70) and CBM3 (aa residue 131-212), while in B. thuringiensis only GH8 catalytic domains were identified (aa residue 30 -370). The protein motif of the endoglucanase gene B. subtilis and B. thuringiensis had a high similarity characterized by the asn_glycosylation, camp_phospho_site, ck2_phospho_site, myristyl and pkc_phospho_site motif.