ribonuclease/dental caries

The crystal structure of Escherichia coli ribonuclease HI has a cavity near Val-74 within the protein core. In order to fill the cavity space, we constructed two mutant proteins, V74L and V74I, in which Val-74 was replaced with either Leu or Ile, respectively. The mutant proteins are stabilized, as

Seven hydrophobic residues ranging in size from glycine to phenylalanine have been substituted for the wild-type methionine residue at position 13 in a 15-residue truncated version (S15) of S-peptide, the small component of ribonuclease S. Complexes of both S-15 and the seven variants with S-protein

The size of the cavity around Ser68 of Escherichia coli ribonuclease HI was modulated by amino acid substitutions to examine the effects on the stability of the enzyme. Five mutant proteins, Ser68----Gly, Ser68----Ala, Ser68----Thr, Ser68----Val and Ser68----Leu, were constructed. Each of the mutant

The binding of a moderate inhibitor, 3'-N-piperidine-4-carboxyl-3'-deoxy-ara-uridine, to ribonuclease A has been studied by X-ray crystallography at 1.7A resolution. Two inhibitor molecules are bound in the central RNA binding cavity of RNase A exploiting interactions with residues from peripheral

The conformational changes of ribonuclease A due to thermal and guanidine hydrochloride denaturation were monitored by means of precise density and sound velocity measurements. It was found that the apparent molar volume decreased but the adiabatic compressibility increased on thermal denaturation

Bull seminal vesicle ribonuclease, when added in vitro to the suspension of ascitic leukaemic cells EL-4 and BP-8 for 2 hours at 37 degrees C and then transplanted to the abdominal cavities of mice, inhibitied the proliferation of these cells in vivo. When the temperature of the medium was decreased

The relationship between the structural stability and the internal motions of proteins was investigated through measurements of 15N relaxation and hydrogen-deuterium exchange rates of ribonuclease HI from Escherichia coli and its thermostable quintuple mutant (Gly23-->Ala, His62-->Pro, Val74-->Leu,

In the present work, we have thermodynamically characterized the thermally induced unfolding of 20 variants of bovine pancreatic ribonuclease A (RNase A) to experimentally describe the residues and the regions that are critical for the stability of the enzyme. The achieved results, complemented with

Poly(A)-specific ribonuclease (PARN) is a homodimeric, processive, and cap-interacting 3' exoribonuclease that efficiently degrades eukaryotic mRNA poly(A) tails. The crystal structure of a C-terminally truncated PARN in complex with m(7)GpppG reveals that, in one subunit, m(7)GpppG binds to a

Salt ions affect protein stability in a variety of ways. In general, these effects have either been interpreted from a charge solvation/charge screening standpoint or they have been considered to be the result of ion-specific interactions with a particular protein. Recent theoretical work suggests

A series of tetra-substituted 'pseudo' dipeptide ligands of cyclen (1,4,7,10,-tetraazacyclododecane) and a tri-substituted 3'-pyridine ligand of cyclen, and the corresponding lanthanide(III) complexes were synthesised and characterised as metallo-ribonuclease mimics. All complexes were shown to

Ribonuclease T1 was purified from an Escherichia coli overproducing strain and co-crystallized with adenosine 2'-monophosphate (2'-AMP) by microdialysis against 50% (v/v) 2-methyl-2,4-pentanediol in 20 mM sodium acetate, 2 mM calcium acetate, pH 4.2. The crystals have orthorhombic space group

Bovine seminal ribonuclease (BS-RNase) is a peculiar member of the pancreatic-like ribonuclease superfamily endowed with unique biological functions. It has been shown that native BS-RNase is a mixture of two distinct dimeric forms. The most abundant form is characterised by the swapping of the

The glycosylated form of bovine pancreatic ribonuclease, RNase B, was crystallized from polyethylene glycol 4000 at low ionic strength in space group C2 with unit cell dimensions of a = 101.81 A, b = 33.36 A, c = 73.60 A, and beta = 90.4 degrees. The crystals, which contained two independent

The lanthanide ion based macrocyclic complexes 1.Ln mimic the hydrophobic nature of ribonucleases, where the lanthanide ions induce the formation of a hydrophobic cavity for 1, giving rise to a large order of magnitude enhancement in the hydrolytic cleavage of HPNP.