caa a22 4500 477132367 CHVBK 20180405111707.0 cr unu---uuuuu 170330e19970901xx s 000 0 eng 10.1023/A:1018395510334 doi (NATIONALLICENCE)springer-10.1023/A:1018395510334 Role of metal cations in the regulation of NADP-linked isocitrate dehydrogenase from porcine heart [Elektronische Daten] [Keiko Murakami, Shouko Iwata, Miyako Haneda, Masataka Yoshino] The regulatory role of divalent metal cations in the NADP-linked isocitrate dehydrogenase (EC 1.1.1.42) from porcine heart was analysed. Saturation curves with respect to the substrate threo-Ds-isocitrate complexed with the metals including manganous, cadmium, cobaltous and zinc ions showed sigmoid relationships characteristic of allosteric enzymes. The Hill's interaction coefficients were 1.90, 1.75, 1.28 and 1.12, respectively. Saturation kinetics of the substrate-metal complexes including magnesium, ferrous and nickel ions exhibited normal hyperbolic curves with Hill's coefficients of 1. The ionic radii of metal cations were closely correlated with the maximal velocity, the enzyme affinity and the Hill's n values for the substrate-metal complexes. Cooperative interactions of metal-substrate complexes with NADP-isocitrate dehydrogenase are discussed in relation to the sites of the enzyme for the binding of the metal-substrate complex. Chapman and Hall, 1997 cooperativity nationallicence ionic radii nationallicence metal-isocitrate nationallicence NADP-isocitrate dehydrogenase nationallicence Murakami Keiko Department of Biochemistry, Aichi Medical University, Aichi, Japan aut Iwata Shouko Department of Biochemistry, Aichi Medical University, Aichi, Japan aut Haneda Miyako Department of Biochemistry, Aichi Medical University, Aichi, Japan aut Yoshino Masataka Department of Biochemistry, Aichi Medical University, Aichi, Japan aut Biometals Kluwer Academic Publishers 10/3(1997-09-01), 169-174 0966-0844 10:3<169 1997 10 10534 https://doi.org/10.1023/A:1018395510334 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1023/A:1018395510334 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Murakami Keiko Department of Biochemistry, Aichi Medical University, Aichi, Japan aut NATIONALLICENCE 700 1- Iwata Shouko Department of Biochemistry, Aichi Medical University, Aichi, Japan aut NATIONALLICENCE 700 1- Haneda Miyako Department of Biochemistry, Aichi Medical University, Aichi, Japan aut NATIONALLICENCE 700 1- Yoshino Masataka Department of Biochemistry, Aichi Medical University, Aichi, Japan aut NATIONALLICENCE 773 0- Biometals Kluwer Academic Publishers 10/3(1997-09-01), 169-174 0966-0844 10:3<169 1997 10 10534 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer