Role of Arginine Residues of D-Aminoacylase from Alcaligenes xylosoxydans subsp. xylosoxydans A-6
To investigate the role of arginine in the folding of D-aminoacylase, seven arginine residues, R26, R152, R296, R302, R354, R377, and R391, among twelve arginine residues highly conserved in D-aminoacylase, N-acyl-D-aspartate amidohydrolase (D-AAase), and N-acyl-D-glutamate amidohydrolase (D-AGase) from Alcaligenes xylosoxydans subsp. xylosoxydans A-6 (Alcaligenes A-6) were substituted with lysine by site-directed mutagenesis. The mutants, R26K, R152K, R296K, and R302K were identified as mutations that increase partitioning of the enzyme into inclusion bodies. No mutants with substitutions within the carboxyterminal segment were found to increase partitioning into inclusion bodies (R354K, R377K, and R392K). These results suggest that arginine residues that position between the N-terminus and central region can play an important role in facilitating folding or stabilizing the structure of D-aminoacylase. By anaerobic cultivation, the production level of R302K in the soluble fraction was improved. Coexpression of the DnaKDnaJ- GrpE chaperone assisted the folding of R302K, and reduced the effect of the aeration conditions on the solubility of R302K. We hypothesized that R302K requires a larger amount of chaperones for efficient folding than the wild type enzyme.
More about this publication?
Protein & Peptide Letters publishes short papers in all important aspects of protein and peptide research, including structural studies, recombinant expression, function, synthesis, enzymology, immunology, molecular modeling, drug design etc. Manuscripts must have a significant element of novelty, timeliness and urgency that merit rapid publication. Reports of crystallisation, and preliminary structure determinations of biologically important proteins are acceptable. Purely theoretical papers are also acceptable provided they provide new insight into the principles of protein/peptide structure and function.
Open access content
Free trial content