RESUMEN
A4 (muscle-type) Lactate Dehydrogenase was purified to homogeneity from Dermochelys coriacea. The steady-state kinetic features of the enzyme show remarkable similarities with those displayed by many other heterothermal LDH's from cold-blooded vertebrates.
Asunto(s)
L-Lactato Deshidrogenasa/metabolismo , Músculos/enzimología , Tortugas/metabolismo , Animales , Isoenzimas , Cinética , L-Lactato Deshidrogenasa/aislamiento & purificación , Tortugas/anatomía & histologíaRESUMEN
1. By using affinity chromatography and chromatofocusing analysis at least two major glutathione transferases, named GST II and GST III can be isolated from Gammarus italicus. 2. GST II has an isoelectric point at pH 5.0 and is composed of two subunits with an apparent molecular mass of 28 KDa. 3. GST III which has an isoelectric point at pH 4.6 was found to be an heterodimer of 27 KDa and 28 KDa. 4. The 28 KDa subunit cross-reacted in immunoblotting analysis with antisera raised against pi class GST, whereas none of the antisera raised against alpha, mu and pi class GSTs cross-reacted with the 27 KDa subunit.
Asunto(s)
Crustáceos/enzimología , Glutatión Transferasa/aislamiento & purificación , Animales , Monitoreo del Ambiente , Glutatión Transferasa/química , Glutatión Transferasa/inmunología , Inmunoquímica , Punto Isoeléctrico , Isoenzimas/química , Isoenzimas/inmunología , Isoenzimas/aislamiento & purificación , Modelos Biológicos , Peso MolecularRESUMEN
1. Like other lamprey species, Lampetra planeri displays LDH chains of a single type. Since lampreys are more related to vertebrates than myxines, which do have usual A and B monomers, we suspect that either a gene inactivation or a gene loss occurred in the former group. 2. The characterization of the enzyme gave interesting results. From the standpoint of its affinity for ion exchangers, it behaves as if it is composed of A-type chains. 3. From the standpoint of substrate and product inhibition, it resembles much more closely the B containing isozyme. 4. Since literature reports that the other known single-chained LDH's from lampreys are definitely of the A type, we suggest the possibility that L. planeri enzyme underwent some orthologous evolution which brought it to resemble the heart isozyme.