Generation of a catalytic antibody by site-directed mutagenesis

Generation of a catalytic antibody by site-directed mutagenesis.

A hybrid Fv fragment of the dinitrophenyl-binding immunoglobulin A (IgA), MPOC315, has been generated by reconstituting a recombinant variable light chain (VL) produced in Escherichia coli with a variable heavy chain (VH) derived from the antibody. The Tyr34 residue of VL was substituted by His in order to introduce a catalytic imidazole into the combining site for the ester hydrolysis. The His...

Construction of a recombinant vector for site-directed mutagenesis in Salmonella typhimurium

BACKGROUND: Among all common techniques in sitedirectedmutagenesis, λ Red recombinase system has beenwidely used to knock out chromosomal genes in bacteria. In thismethod, there is always the risk of DNA Linear digestion byhost's restriction enzymes that leads to the low frequency ofrecombination. OBJECTIVES:To overcome this, we constructeda recombinant vector to disrupt phoP gene in Salmonella...

Construction and Expression of Hepatitis B Surface Antigen Escape Variants within the "a" Determinant by Site Directed Mutagenesis

Background: The antibody response to hepatitis B surface antigen (HBsAg) controls hepatitis B virus infection. The "a" determinant of HBsAg is the most important target for protective antibody response, diagnosis and immunoprophylaxis. Mutations in this area may induce immune escape mutants and affect the performance of HBsAg assays. Objectives: To construct clinically relevant recombinant muta...

Serratia marcescens B4A chitinase thermostability enhancement by S390I QuikChange site directed mutagenesis

Thermostable chitinases are useful for industrial and biotechnological applications. This paper reports the stabilization of chitinase from Serratia marcescens B4A through rational mutagenesis. Changing of Ser 390 to Ile in S. marcescens. The stabilization was enhanced through entropic stabilization by reduction of the loop length and also by increasing of the beta chain length. With this repla...

Generation of the mutant library and site directed mutagenesis