Properdin factor D,1 a 23,500 tool wt euglobulin (6), interacts with properdin factor B and cobra venom factor (CoVF) to generate the CoVF-dependent C3 convertase which cleaves C3 (7) and activates the terminal complement components, C5-C9 (8). Fluid phase C3b, the major cleavage fragment of C3, interacts with factors B and D in a manner analogous to CoVF to form a fluid phase C3b-dependent C3 ...

Eby, D. & Kirtley, M. E. (1971) Biochemistry 10,2677-2682 Fuller-Noel, J. K. & Schumaker, V. W. (1972) J. Mol. Biol. 68,523-532 Gennis, L. S. (1976) Proc. Natl. Acad. Sci. U.S.A. 73, 3928-3932 Harrigan, P. J. & Trenthami, D. R. (1971) Biochem. J . 124, 573-580 Hams, J. I. & Polgar, L. (1965) J. Mol. Biol. 14, 630-633 Harris, J. I. & Waters, M. (1976) Enzymes 3rd Ed. 23, 1-50 Kirschner, K. (1971...

Egg-white avidin was treated with 1 -fluoro-2,4-dinitrobenzene. Modification of an average of one lysine residue per avidin subunit caused the complete loss of biotin binding. Tryptic peptides obtained from the 2,4-dinitrophenylated avidin were fractionated by reversed-phase h.p.l.c. Three peptides contained the 2,4-dinitrophenyl group. Amino acid analysis revealed that lysine residues 45, 94 a...

(A)BC excinuclease of Escherichia coli removes damaged nucleotides from DNA by hydrolyzing the 8th phosphodiester bond 5’ and the 5th phosphodiester bond 3‘ to the modified base. The activity results from the ordered action of UvrA, UvrB, and UvrC proteins. The role of UvrA is to help assemble the UvrB .DNA complex, and it is not involved in the actual incision reactions which are carried out b...