caa a22 4500 469080434 CHVBK 20180323132948.0 cr unu---uuuuu 170328e19920201xx s 000 0 eng 10.1007/BF00554427 doi (NATIONALLICENCE)springer-10.1007/BF00554427 Characterization of two electrophoretic lactate dehydrogenase-A mutants in Mus musculus [Elektronische Daten] [Siegbert Merkle, Walter Pretsch] Two lactate dehydrogenase (LDH) mutations were recovered independently among offspring of ethylnitrosourea-treated male mice by screening for alterations of isoelectric focusing pattern in liver homogenates. Investigations of physicochemical and kinetic properties of the mutant enzymes indicated that the mutant traits resulted from point mutations at theLdh-1 structural locus. Therefore, the new alleles were designatedLdh-1 a-m5Neu andLdh-1 a-m6Neu, respectively. Both mutant alleles code for proteins which exhibit an altered stability to heat, in addition to changes in isolectric focusing pattern and a reduction in anodal electrophoretic mobility. While LDH-Aa-m5Neu proteins are markedly less heat stable, LDH-Aa-m6Neu proteins are more heat stable than the wild-type enzyme. Furthermore, a small elevation ofK m for pyruvate, a slightly reduced inhibition by high pyruvate concentrations, and a slight acidic shift of the pH activity profile distinguish LDH-Aa-m6Neu from both wild-type and LDH-Aa-m5Neu enzymes. Significant alterations of LDH activity were detected in some tissues from LDH-Aa-m5Neu individuals but not in those from LDH-Aa-m6Neu animals. Erythrocytes and blood of LDH-Aa-m5Neu mutants revealed activity levels which were reduced by approximately 6 and 13% compared with those of wild types in heterozygous and homozygous individuals, respectively. In addition, an elevation of approximately 6% in LDH activity was found in skeletal muscle in homozygous mutants. Consistent with the unaltered or only slightly altered LDH activity in tissues, the genetic as well as the physiological characterization yielded no easily detectable effects from either mutation on metabolism or fitness of the affected individuals. Plenum Publishing Corporation, 1992 lactate dehydrogenase-A nationallicence electrophoretic mutants nationallicence mouse nationallicence structural characteristics nationallicence isoelectric focusing nationallicence Merkle Siegbert Institut für Säugetiergenetik, GSF-Forschungszentrum für Umwelt und Gesundheit GmbH, Ingolstädter Landstr 1, 8042, Neuherberg, Germany aut Pretsch Walter Institut für Säugetiergenetik, GSF-Forschungszentrum für Umwelt und Gesundheit GmbH, Ingolstädter Landstr 1, 8042, Neuherberg, Germany aut Biochemical Genetics Kluwer Academic Publishers-Plenum Publishers 30/1-2(1992-02-01), 49-59 0006-2928 30:1-2<49 1992 30 10528 https://doi.org/10.1007/BF00554427 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00554427 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Merkle Siegbert Institut für Säugetiergenetik, GSF-Forschungszentrum für Umwelt und Gesundheit GmbH, Ingolstädter Landstr 1, 8042, Neuherberg, Germany aut NATIONALLICENCE 700 1- Pretsch Walter Institut für Säugetiergenetik, GSF-Forschungszentrum für Umwelt und Gesundheit GmbH, Ingolstädter Landstr 1, 8042, Neuherberg, Germany aut NATIONALLICENCE 773 0- Biochemical Genetics Kluwer Academic Publishers-Plenum Publishers 30/1-2(1992-02-01), 49-59 0006-2928 30:1-2<49 1992 30 10528 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer