When a drug interacts with its receptor, the nonpolar substituent of and receptor proteins attract each other because they have opposite magnitude respect to other. X-rays structure studies reflected that S2/S2’ pocket in HIV-1 protease enzyme are essentially hydrophobic. The residues make up these pockets Val-32, Ile-47, Ile-50, Ile-84 monomeric polypeptidic unit enzyme. Δπdr ΔSASAdr been used...

Outer membrane phospholipase A (OMPLA) is an integral membrane enzyme that catalyses the hydrolysis of phospholipids. Enzymatic activity is regulated by reversible dimerisation and calcium-binding. We have investigated the role of calcium by X-ray crystallography. In monomeric OMPLA, one calcium ion binds between two external loops (L3L4 site) at 10 A from the active site. After dimerisation, a...

For more than 15 years, the tautomerase active site of macrophage migration inhibitory factor (MIF) and its catalytic residue Pro1 have been being targeted for the development of therapeutics that block activation of its cell surface receptor, CD74. Neither the biological role of the MIF catalytic site nor the mechanistic details of CD74 activation are well understood. The inherently unstable s...

We study equilibrium properties of a catalytically-activated annihilation A + A → 0 reaction taking place on a one-dimensional chain of length N (N → ∞) in which some segments (placed at random, with mean concentration p) possess special, catalytic properties. Annihilation reaction takes place, as soon as any two A particles land onto two vacant sites at the extremities of the catalytic segment...

Submitochondrial particles from beef heart, washed with dilute solutions of KCl so as to activate the latent, membrane-bound ATPase, F1, may be used to study single site catalysis by the enzyme. [gamma-32P]ATP, incubated with a molar excess of catalytic sites, a condition which favors binding of substrate in only a single catalytic site on the enzyme, is hydrolyzed via a four-step reaction mech...

Glycoside hydrolases often possess carbohydrate-binding modules (CBMs) in addition to their catalytic domains, which help target the enzymes to appropriate substrates and thereby increase their catalytic efficiency. Sialidases hydrolyse the release of sialic acid from a variety of glycoconjugates and play significant roles in the pathogenesis of a number of important diseases. The sialidase fro...

Human paracaspase has been predicted to be a member of the protein structural fold that encompasses protease clan CD. To determine whether paracaspase has catalytic activity we have expressed the region corresponding to the catalytic domain and used protease activity-based chemical probes to profile the putative active site. A leucine-based acyloxymethyl ketone probe that covalently labels cyst...

1. l-Serine was shown to be a highly specific inhibitor of 3-phosphoglycerate dehydrogenase. 2. 3-Phosphoglycerate dehydrogenase is cold-labile with respect to its catalytic activity and to sensitivity to serine. 3. l-Serine protects the catalytic site as well as the inhibitor site. 4. Glycerol protects the catalytic site as well as the inhibitor site. 5. Serine acts as a ;classical' non-compet...

The intrinsic tryptophan fluorescence of Schizosaccharomyces pombe mitochondrial F1 is a very sensitive probe to differentiate nucleotide binding to catalytic and noncatalytic sites (Divita, G., Di Pietro, A., Roux, B., and Gautheron, D. C. (1992) Biochemistry 31, 5791-5798), the catalytic site saturation producing quenching of Trp-257 fluorescence (Divita, G., Jault, J.-M., Gautheron, D. C., a...