[Distribution of aromatic amino acid residues according to the character of their microenvironment and the dynamics of the conformational properties of the protein molecule C1q].
The distribution of aromatic amino acid residues in the Clq molecule according to their microenvironment was studied by the methods of difference thermal and solvent perturbation spectroscopy, fluorescence and chemical modification. Out of the three tryptophan residues located in the globular part of A- chain one residue is completely exposed on the surface, while other two are only partially exposed to a solvent. Chemical modification of tryptophanyls significantly affects the hemolytic activity of Clq, that may evidence for the formation of immunoglobulin-binding sites with participation of A- chains as well as for the location of, at least, one of the three tryptophan residues in A- chain close to the immunoglobulin-binding site or even participation in the formation of the latter. The average rotation relaxation time of tryptophanyls estimated from the data on fluorescence is 210 +/- 10 ns. It specifies mobility of the globular and collagen parts of the molecule.
Ul'ianov
V D
VD
Mogutnova
V A
VA
Surovtsev
V I
VI
Shmatchenko
N A
NA
Sukhomudrenko
A G
AG
D000596:Amino Acids / Q000032:analysis*; D003166:Complement Activating Enzymes / Q000032:analysis*; D003172:Complement C1 / Q000032:analysis*; D015922:Complement C1q; D011487:Protein Conformation; D013053:Spectrophotometry; D014364:Tryptophan / Q000032:analysis
D000596:Amino Acids; D003172:Complement C1; D015922:Complement C1q; D014364:Tryptophan; D003166:Complement Activating Enzymes
Raspredelenie aromaticheskikh aminokislotnykh ostatkov po kharakteru mikrookruzheniia i dinamicheskie konformatsionnye svoĭstva molekuly belka C1q.