Human Dipeptidyl Peptidase III: the Role of Asn406 in Ligand Binding and Hydrolysis

Špoljarić, Jasminka; Tomić, Antonija; Vukelić, Bojana; Salopek Sondi, Branka; Agić, Dejan; Tomić, Sanja; Abramić, Marija (2011) Human Dipeptidyl Peptidase III: the Role of Asn406 in Ligand Binding and Hydrolysis. Croatica Chemica Acta, 84 (2). pp. 259-268. ISSN 0011-1643

PDF - Published Version Download (5MB)

Abstract

Human dipeptidyl peptidase III (DPP III) is a member of the zinc-metallopeptidase family M49 with a role in intracellular protein catabolism. Ligand-free crystal structure of yeast and human orthologues provided insight into the enzyme's active center and enabled some assumptions about the enzyme - substrate interactions. The molecular modeling performed for human and yeast DPP III indicated involvement of Asn406 and Asn415, respectively in ligand binding. To investigate further the role of this asparagine residue, conserved in all eukaryotic M49 peptidases, a site-directed mutagenesis of human DPP III was carried out. Replacement of Asn406 with Gln, but not with Ser, resulted in a large decrease in the enzyme's binding affinity for competitive peptide inhibitor and in catalytic efficiency. Molecular dynamics simulations performed for enzyme-substrate complexes, revealed changed coordination of the active-site zinc ion and the orientation of the catalytically important His568, in N406Q, but not in the N406S complexes.

Item Type:	Article
Uncontrolled Keywords:	dipeptidyl peptidase III; molecular dynamics; peptidase family M49; protein structure-function; site-directed mutagenesis; reactive cysteine residues; particle mesh ewald; aminopeptidase-iii; molecular-cloning; substrate-binding; purification; proteins; coordination; specificity; simulation
Subjects:	NATURAL SCIENCES > Chemistry
Divisions:	Division of Molecular Biology Division of Organic Chemistry and Biochemistry Division of Physical Chemistry
Projects:	Project title Project leader Project code Project type Molekularna enzimologija i proteinske interakcije hidrolaza [22] Marija Abramić 098-1191344-2938 MZOS Proučavanje biomakromolekula računalnim metodama i razvoj novih algoritama [113604] Sanja Tomić 098-1191344-2860 MZOS Molekularna regulacija biljnog razvitka [200002] Branka Salopek-Sondi 098-0982913-2829 MZOS
Depositing User:	Marija Abramić
Date Deposited:	16 Oct 2013 08:35
URI:	http://fulir.irb.hr/id/eprint/793
DOI:	10.5562/cca1808

Actions (login required)

View Item