Direct photoaffinity labeling by nucleotides of the apparent catalytic site on the heavy chains of smooth muscle and Acanthamoeba myosins
The heavy chains of Acanthamoeba myosins, IA, IB and II, turkey gizzard myosin, and rabbit skeletal muscle myosin subfragment-1 were specifically labeled by radioactive ATP, ADP, and UTP, each of which is a substrate or product of myosin ATPase activity, when irradiated with uv light at 0/sup 0/C. With UTP, as much as 0.45 mol/mol of Acanthamoeba myosin IA heavy chain and 1 mol/mol of turkey gizzard myosin heavy chain was incorporated. Evidence that the ligands were associated with the catalytic site included the observations that reaction occurred only with nucleotides that are substrates or products of the ATPase activity; that the reaction was blocked by pyrophosphate which is an inhibitor of the ATPase activity; that ATP was bound as ADP; and that label was probably restricted to a single peptide following limited subtilisin proteolysis of labeled Acanthamoeba myosin IA heavy chain and extensive cleavage with CNBr and trypsin of labeled turkey gizzard myosin heavy chain.
- OSTI ID:
- 6172038
- Journal Information:
- J. Biol. Chem.; (United States), Vol. 256:1
- Country of Publication:
- United States
- Language:
- English
Similar Records
Photoaffinity labeling of myosin subfragment-one-with 3'(2')-O-(4-benzoyl)benzoyl adenosine 5'-triphosphate
Serine-324 of myosin's heavy chain is photoaffinity-labeled by 3 prime (2 prime )-O-(4-benzoylbenzoyl)adenosine triphosphate
Related Subjects
59 BASIC BIOLOGICAL SCIENCES
MYOSIN
LABELLING
PHOTOCHEMICAL REACTIONS
ADP
AMOEBA
AMP
ATP
ATP-ASE
ENZYME ACTIVITY
ENZYME INHIBITORS
FOWL
METABOLISM
MUSCLES
NUCLEOTIDES
PEPTIDES
PYROPHOSPHATES
RABBITS
SUBSTRATES
TRYPSIN
ULTRAVIOLET RADIATION
ACID ANHYDRASES
ANIMALS
BIRDS
CHEMICAL REACTIONS
ELECTROMAGNETIC RADIATION
ENZYMES
GLOBULINS
HYDROLASES
INVERTEBRATES
MAMMALS
MICROORGANISMS
ORGANIC COMPOUNDS
OXYGEN COMPOUNDS
PEPTIDE HYDROLASES
PHOSPHOHYDROLASES
PHOSPHORUS COMPOUNDS
PROTEINS
PROTOZOA
RADIATIONS
SARCODINA
SERINE PROTEINASES
VERTEBRATES
560111* - Radiation Effects on Biochemicals- In Vitro- (-1987)
550200 - Biochemistry