Separation and characterization of four enzyme forms of beta-galactosidase from Saccharomyces lactis.

beta-Galactosidase from Saccharomyces lactis has been purified to serve as a model for the kinetic behavior of human lactase in adult lactase deficiency. Enzymes from both species are neutral and follow Michaelis-Menten kinetics. beta-Galactosidase of S.

Caiman crocodylus hemoglobin. Complete primary structures of alpha and beta chains; phylogenic and regulatory aspects.

In some reptiles, the hemoglobin oxygen affinity is lowered by CO2 and not by the usual phosphate cofactors. To understand the molecular mechanism of this regulation, Caiman crocodylus hemoglobin's primary structure has been determined. The alignment of the 141 residues of the alpha chain as well as the 146 of the beta chain were obtained by classical method of sequence analysis and are compared with some mammalian, avian, amphibian, and fish hemoglobin chains.