Characterization of a Chitinase (Chit62) from Serratia marcescens B4A and Its Efficacy as a Bioshield Against Plant Fungal Pathogens

Abstract

Chitinases have been suggested to be involved in pathogen-antagonist interaction during biological control progress of plant pathogenic fungi. Here, a recombinant bacterial chitinase originally from Serratia marcescens B4A was produced, purified, and assayed biochemically to ascertain the activity and determine the kinetics parameters. Active enzyme was used to determine its biocontrol features against fungal phytopathogens. The results demonstrated that the optimum pH and temperature for the enzyme activity were 6.0 and 55 °C, respectively. The K(m) and V(max) values were 3.30 mg ml(-1) and 0.92 units, respectively. The recombinant chitinase was demonstrated to be highly active in controlling fungal pathogens.

RETRACTED: Purification and characterisation of an acidic and antifungal chitinase produced by a Streptomyces sp.

“…Yong et al (2005) reported a V max value of 10.53 U min À1 mg À1 for a Sanguibacter sp. while Babashpour et al (2012) reported a V max value of 10.53 U for Serratia marcescens using colloidal chitin as substrate.…”

“…In accordance with the activity staining results, the chitinase enzyme in the ammonium sulphate purified fraction showed a clear band by zymography, confirming that it was a chitinase. Molecular masses of bacterial chitinases generally range from 30 to 80 kDa (Annamalai et al, 2010;Margino et al, 2010;Babashpour et al, 2012;Jiang et al, 2012;Brzezinska et al, 2013;Dai et al, 2011). The purified enzyme was analysed by SDS-PAGE and activity staining of the gel (chitin zymography) shown in Fig.…”

“…Percent relative activity 10% 20% (Joo, 2005;Liu et al, 2010;Rabeeth et al, 2011;Babashpour et al, 2012;Jankiewicz et al, 2012;Nagpure and Gupta, 2013). A Streptomyces sp.…”

Characterization, antifungal activity, and cell immobilization of a chitinase from Serratia marcescens MO-1

“…Since fungal cell walls and insect exoskeletons contain chitin, a homopolymer of β-1,4-linked N-acetyl-Dglucosamine residues as a major structural component, chitinases have been reported for their potential as biopesticides for the control of the plant diseases caused by various phytopathogenic fungi (3,4) and insect pests (1,5). Chitin is degraded into disaccharides and larger oligomeric saccharides by the action of chitinases (EC 3.2.1.14) through hydrolysis of the β-(1,4)-linkages (6), and these enzymes have been divided into 2 separate families, GH18 and GH19, based on amino acid sequences and their catalytic mechanisms (4).…”

YvoA and CcpA Repress the Expression of chiB in Bacillus thuringiensis

“…Several studies have reported that chitinases generated by Bt are involved in its antifungal activity and can enhance the insecticidal activity of Bt strains (7)(8)(9)(10). Many studies have reported the expression and application of chitinases in microorganisms (11)(12)(13)(14)(15). However, reports on the regulation mechanism of chitinase genes are scarce.…”