The alkaline phosphatase (AP) is a bi-metalloenzyme of potential applications in biotechnology and bioremediation, in which phosphate monoesters are nonspecifically hydrolysed under alkaline conditions to yield inorganic phosphate. The hydrolysis occurs through an enzyme intermediate in which the catalytic residue is phosphorylated. The reaction, which also requires a third metal ion, is propos...

Pentapeptides containing either L-methionine, L-proline, L-arginine, or L-lysine as central residue in the pattern glycylglycyl-X-glycylglycine have been studied at natural abundance by proton-decoupled 13C! nuclear magnetic resonance spectroscopy. Resonances were assigned in most cases by comparison with the free amino acids and by detailed observation of change in chemical shift with pH over ...

The HIV-1 nucleocapsid protein (NCp7) is a small, highly conserved protein with two zinc-binding domains that are essential for the protein's function. Molecules that bind to and inactivate NCp7 are currently being evaluated as new antiviral drugs. In particular, derivatives based on a 2-mercaptobenzamide thioester template have been shown to specifically eject zinc from the C-terminal zinc-bin...

Reversible post-translational protein modifications such as SUMOylation add complexity to cardiac transcriptional regulation. The homeodomain transcription factor Nkx2-5/Csx is essential for heart specification and morphogenesis. It has been previously suggested that SUMOylation of lysine 51 (K51) of Nkx2-5 is essential for its DNA binding and transcriptional activation. Here, we confirm that S...

The AMP-forming acyl coenzyme A (acyl-CoA) synthetases are a large class of enzymes found in both anabolic and catabolic pathways that activate fatty acids to acyl-CoA molecules. The protein acetyltransferase (Pat) from Rhodopseudomonas palustris (RpPat) inactivates AMP-forming acyl-CoA synthetases by acetylating the ε-amino group of a conserved, catalytic lysine residue. In all of the previous...

The kinetic properties of bovine liver glutamate dehydrogenase have been examined as a function of pyridoxal phosphate modification, this reagent having been previously shown to react specifically with lysine-97 of the tentative sequence proposed by Smith et al. ((1970) Proc. Nat. Acad. Sci. U. S. A. 67, 724). It is found that partial modification (two to three groups per six chains in the acti...

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...

Several specific modifications, both proteolytic and chemical, have been performed on RNase A. The ability of each of these RNase A derivatives to bind the human placental RNase inhibitor has been determined in competition binding assays. The interaction depends upon the native conformation of the enzyme. Loss of active site residues His-12 and His-119, along with auxiliary residues Lys-7, Phe-...