ABSTRACT
Homogenous yeast (Endomycopsis sp. 20-9) glucoamylase was isolated from cultural medium. The homogeneity of the enzyme preparation is demonstrated by means of polyacrylamide gel disc electrophoresis, isofocusing and ultracentrifugation. Amino acid composition, molecular weight (53 000), sedimentation constant (4.3S) and isoelectric point (pI 3.80-3.82) of the enzyme are determined. Glucoamylase is found to be glucoprotein.
Subject(s)
Ascomycota/enzymology , Glucan 1,4-alpha-Glucosidase/isolation & purification , Glucosidases/isolation & purification , Saccharomycetales/enzymology , Amino Acids/analysis , Chemical Phenomena , Chemistry , Glycoproteins/analysis , Isoelectric Point , Molecular WeightABSTRACT
A comparative study of the amino acid composition of histone fractions P4b from slime mold Physarum polycephalum and H2B from calf thymus was carried out using peptide mapping. It was shown that 75% of peptides are common for both proteins. The slime mold histones contain two fractions (P4B and P3), which are homologous to the H2B histone fraction of calf thymus. The data of amino acid analysis, peptide mapping and some physico-chemical properties of the histones revealed the following correlation of the two types of histone fractions: P1--H1, P4a--H3, P4b and P3--H2B, P5-H2A, P6--H4.
Subject(s)
Histones , Myxomycetes/analysis , Physarum/analysis , Thymus Gland/analysis , Amino Acids , Animals , Cattle , Chemical Phenomena , Chemistry , Peptide Fragments , Species SpecificityABSTRACT
The histones from slime mold Physarum polycephalum and calf thymus were characterized in terms of some physico-chemical properties. The molecular weights of six principal histone fractions of Ph. polycephalum were found to be the following: P1--22 700, P3--15 700, P4a--15 000, P4b--14 300, P5--12 800 and P6--10 500. Electrophoretically homogenous histone fractions H1, H2b and H4 of calf thymus and histones P1, P3, P4b and P6 of slime mold were obtained by gel-filtration on Acrylex P-60. These findings suggest that fractions P1, P4a, P4b, P5 and P6 of slime mold Ph. polycephalum are homologus with respect to the histone fractions H1, H3, H2b, H2a and H4 of calf thymus. Only fraction P3 has no corresponding fraction in the calf thymus histones; a fraction corresponding to histone P3 of slime mold was absent.
Subject(s)
Histones , Myxomycetes/analysis , Physarum/analysis , Thymus Gland/analysis , Animals , Cattle , Histones/isolation & purification , Molecular Weight , Species SpecificityABSTRACT
In Physarum polycephalum several degrees of organisation of deoxyribonucleoprotein fibres were found. The complexes of histones and the DNA duplex seem to "be packed" at first into a 100 A fibre and then into a 200 A fibre of DNP. In Ph. polycephalum the electrophoretic mobilities of histone fractions 4 and 6 are comparable to that of fractions f3/f2b and f2a1 of calf thymus, resp. Histone fractions 3 and 5 move a bit faster than fractions f1 and f2a2, resp. Thus, the myxomycete P. polycephalum is similar to higher eukaryotes as concerns the ultrastructure of chromatin and electrophoretic properties of histones.
