Induction of gene expression and chitinolytic activities of putative chitinase gene bacteria Serratia plymuthica UBCF_13

Abstract

Abstract The most dominant disease that causes low production of chili in Indonesia is anthracnose. Anthracnose disease is caused by the pathogenic fungi called Colletotrichum sp. The control of anthracnose disease can be done by using bio fungicides which can be developed from the class of enzymes that degrade pathogenic fungal cell walls. These enzymes are known as hydrolase enzymes, one of which is Chitinase. Chitinase is an enzyme that catalyzes the breakdown of chitin polymer compounds in β-1,4 glycosidic bonds. Chitin is a polymer compound that makes up the fungal cell wall. Chitinolytic bacteria can produce chitinase enzymes. S. plymuthica bacteria produce chitinase enzyme, one of which is putative chitinase [Chi_Put]. The purpose of this study was to express the Chi_Put gene from S. plymuthica UBCF_13 in pGEM-T Easy vector using Escherichia coli BL21 and to test the chitinolytic activity of Chi_Put in degrading chitin in-vitro. Chi_Put gene expression was induced by IPTG and in combination with Mg2+ and Cu2+ metal ions. The highest gene expression was marked by the thickest protein band on the SDS-PAGE visualization with a molecular weight of 47 kDa, namely in the treatment of expression induction with IPTG plus Mg2+ metal ion. The chitinolytic activity of Chi_Put UBCF_13 was tested using solid LB media containing 3% colloidal chitin. The longest clear zone diameter on the last day of observation was the expression induction treatment with Mg2+ with a length of 2.90 cm.