Open AccessStructural and catalytic properties and homology modelling of the human nucleoside diphosphate kinase C, product of the DRnm23 gene
Author(s) -
Erent Muriel,
Gonin Philippe,
Cherfils Jacqueline,
Tissier Pierre,
Raschellà Giuseppe,
Giartosio Anna,
Agou Fabrice,
Sarger Claude,
Lacombe MarieLise,
Konrad Manfred,
Lascu Ioan
Publication year - 2001
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1046/j.1432-1327.2001.2076.doc.x
Subject(s) - nucleoside diphosphate kinase , kinase , biochemistry , map3k7 , protein subunit , microbiology and biotechnology , protein kinase a , protein quaternary structure , chemistry , cyclin dependent kinase 7 , cyclin dependent kinase 2 , homology (biology) , gene , biology
The human DRnm23 gene was identified by differential screening of a cDNA library obtained from chronic myeloid leukaemia‐blast crisis primary cells. The over‐expression of this gene inhibits differentiation and induces the apoptosis of myeloid precursor cell lines. We overproduced in bacteria a truncated form of the encoded protein lacking the first 17 N‐terminal amino acids. This truncated protein was called nucleoside diphosphate (NDP) kinase CΔ. NDP kinase CΔ had similar kinetic properties to the major human NDP kinases A and B, but was significantly more stable to denaturation by urea and heat. Analysis of denaturation by urea, using size exclusion chromatography, indicated unfolding without the dissociation of subunits, whereas renaturation occurred via a folded monomer. The stability of the protein depended primarily on subunit interactions. Homology modelling of the structure of NDP kinase CΔ, based on the crystal structure of NDP kinase B, indicated that NDP kinase CΔ had several additional stabilizing interactions. The overall structure of the two enzymes appears to be identical because NDP kinase CΔ readily formed mixed hexamers with NDP kinase A. It is possible that mixed hexamers can be observed in vivo .