title: Contribution of halophilic nucleoside diphosphate kinase sequence to the heat stability of chimeric molecule.
abstract: A halophilic nucleoside diphosphate kinase from a moderate halophile, Halomonas sp. 593 (593NDK), was found to be resistant to heat treatment, as indicated by the high level of activity recovery after heating at high temperatures. This is due to reversibility of thermal unfolding, not the high melting temperature, of the protein. The highly homologous NDK from non-halophilic organism, Pseudomonas aeruginosa, showed instability against heat treatment. Chimeric molecules consisting of each half of these two NDKs were constructed and characterized for their heat stability. The results showed that the N-terminal half of 593NDK contributes to the heat stability of the proteins. We discuss the possible reason for the observed difference in resistance to heat treatment between the 593NDK and PaNDK and between two chimeric proteins.
authors.affiliation: Applied and Molecular Microbiology, Faculty of Agriculture, Kagoshima University, 1-21-24 Korimoto, Kagoshima 890-0065, Japan.
authors.forename: Hiroko
authors.initials: H
authors.lastname: Tokunaga
authors.forename: Yuuki
authors.initials: Y
authors.lastname: Oda
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Yonezawa
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Arakawa
authors.forename: Masao
authors.initials: M
authors.lastname: Tokunaga
mesh_terms: D000596:Amino Acids / Q000737:chemistry; D002942:Circular Dichroism; D004795:Enzyme Stability; D020632:Halomonas / Q000201:enzymology* / Q000235:genetics; D006358:Hot Temperature; D009701:Nucleoside-Diphosphate Kinase / Q000737:chemistry* / Q000235:genetics* / Q000378:metabolism; D011489:Protein Denaturation; D011550:Pseudomonas aeruginosa / Q000201:enzymology / Q000235:genetics; D011993:Recombinant Fusion Proteins / Q000737:chemistry* / Q000235:genetics* / Q000378:metabolism; D012492:Salts / Q000737:chemistry
chemical_list: D000596:Amino Acids; D011993:Recombinant Fusion Proteins; D012492:Salts; D009701:Nucleoside-Diphosphate Kinase