ABSTRACT
The polypeptide sequence of the unmodified catalase from Penicillium vitale containing 696 amino acid residues was deduced. The sequences of 76 tryptic peptides of the unmodified catalase, 63 tryptic peptides of the catalase with modified Lys residues, 48 peptides resulting from catalase cleavage by the Staphylococcus aureus V8 protease, and 9 fragments obtained by BrCN-treatment were considered, and a comparison with the sequences of other catalases was made.
Subject(s)
Catalase/chemistry , Penicillium/enzymology , Amino Acid Sequence , Chromatography, High Pressure Liquid , Cyanogen Bromide/chemistry , Endopeptidases/chemistry , Lysine/chemistry , Molecular Sequence Data , Peptide Fragments/chemistry , Sequence Homology, Amino Acid , Staphylococcus aureus/enzymologyABSTRACT
An analysis of probability of distribution curves of alpha-helical sites and bends of polypeptide chains of myoglobins in half-water mammals (beaver, nutria, muskrat, otter) carried out in comparison with those of myoglobins of the horse and Sperm whale (X-ray diffraction analysis has revealed their tertiary structure) has revealed a coincidence of the secondary structure sites end bends of the chain in the studied respiratory hemoproteins of muscles. Despite a considerable number of amino acid substitutions the profiles of alpha-helicity and B-bends of the compared proteins are practically identical. This indicates to the "resistance" of the probability curves to amino acid substitutions and to retention of the tertiary structure of myoglobins in evolutionary remote species of the animals.
Subject(s)
Mammals/blood , Muscles/physiology , Myoglobin/chemistry , Respiration/physiology , Amino Acid Sequence , Amino Acids/analysis , Animals , Macromolecular Substances , Probability , Protein Conformation , Sequence Homology , X-Ray DiffractionABSTRACT
Hydrophobicity profiles of myoglobins in the animal species far remote in the evolutionary series are considerably similar. A complete coincidence as to the arrangement of hydrophobic zones along the polypeptide chain in myoglobins of the compared species (from a man to mollusc) is revealed at the beginning of alpha-helix of B-segment and in the area corresponding to a cluster which embodies a heme- bound water molecule, distal histidine E7 being directed to this cluster. The mollusc myoglobin with two absent (as compared to myoglobins of other species) hydrophobic sites differs in the profile of hydrophobicity most of all. It is supposed that hydrophobic nuclei forming the heme circumference create a globule "skeleton" thus pre-setting general spatial structure of the myoglobin molecule, which is very significant for its functional activity.
