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G Camici

Publications and source records attributed to G Camici.

83 records · Page 5Linked to original sources
PubMed1975

Inhibition of horse muscle acylphosphatase by pyridoxal 5'-phosphate.

It has been shown that horse muscle acylphosphatase is inhibited by pyridoxal 5'-phosphate and that the inhibition is pH dependent, reversible and competitive with respect to substrate binding. Spectral analysis on the EI complex demonstrates the presence of a Schiff base. Reduction of the pyridoxal 5'-phosphate-inhibited enzyme with sodium borohydride, followed by amino acid analysis, produces a diminution of the free lysine peak and the appearance of a new peak corresponding to epsilon-pyridoxyllysine. The results suggest that there is at least one NH2-lysyl residue of horse muscle acylphosphatase at or near the active site of the enzyme.

Amino Acids↗
PubMed1975

Nonenzymatic acetylation of histones with acetyl phosphate and acetyl adenylate.

Nonenzymatic acetylation of calf-thymus lysine- and arginine-rich histones was demonstrated to occur when these proteins were incubated with [14C]acetyl phosphate and [14C]acetyl adenylate. The levels of acetylation depend on both pH and on reagent concentration. When acetyl [33P]phosphate and acetyl [3H]adenylate were used as reagents, we found neither histone phosphorylation nor adenylylation. Most of the radioactivity of 14C-labeled acetylated histones was recovered as Ne-acetyllysine. Furthermore, only a small amount of O-bound radioactivity was released by the 14C-labeled acetylated arginine-rich histone during treatment with hydroxylamine. Experiments on the acetylation of histones, in the presence of increasing salt concentration, gave different results for the two acetylating agents.

Acetates↗
PubMedDate not supplied

Horse muscle acylphosphatase: a more rapid purification procedure and crystallization.

A crystalline acyl phosphatase has been obtained from horse muscle. The enzyme purified by a modified procedure which allowed to obtain a larger yield with respect to a method previously developped in this laboratory, was homogeneous by disc electrophoresis on polyacrylamide gel. Crystals of this enzymatic protein have been obtained by the addition of ammonium sulphate to around 52% saturation.

Acid Anhydride Hydrolases↗
PubMedDate not supplied

Horse heart acylphosphatase: purification and characterization.

The use of an affinity chromatography step performed with an immunoadsorbent consisting of anti-horse muscle acylphosphatase antibodies covalently linked to Sepharose 4B allowed us to purify horse heart acylphosphatase in a very rapid and efficient fashion. As in skeletal muscle, also in heart the enzyme is present as both a mixed disulfide with glutathione and a S-S dimer. The abundance of these forms in heart is quite lower than in skeletal muscle. The comparison of the molecular forms so purified with those obtained from horse skeletal muscle showed the same aminoacid composition, tryptic fingerprint, together with strictly similar apparent molecular weight and main kinetic parameters, supporting the conclusion that the acylphosphatase present in heart is the same enzyme as that purified from skeletal muscle.

Acid Anhydride Hydrolases↗
PubMedDate not supplied

The complete amino acid sequence of bovine skeletal muscle acylphosphatase.

The primary structure of bovine skeletal muscle acylphosphatase was determined by performing the sequence analyses of the complete series of tryptic peptides. The amino acid composition of the entire series of peptic peptides was used to reconstruct the sequence by the overlapping method. The proposed structure is further confirmed by analogy with known amino acid sequences of acylphosphatase from skeletal muscle of other vertebrate species. The length of the polypeptide chain is 98 residues, identical to the length of the enzymes from other known mammalian species, but different from that found in turkey. The enzyme is NH2-acetylated and a comparison with the analogous molecular forms from other vertebrate species indicates that there are several long polypeptide stretches strictly conserved (93-97% identical position among mammals, and about 80% between calf and turkey enzymes).

Acid Anhydride Hydrolases↗
PubMedDate not supplied

[Localized scleroderma in childhood].

Scleroderma is a rare disease in children: the clinical presentation in childhood is even more varied than in adult life. It is characterized by 'hard skin' with cutaneous features including hypo- and hyperpigmentation, thickening or thinning and loss of elasticity. It ranges from circumscribed and self-limiting pigmentary disorders to disabling and disfiguring involvement of an extremity and a rapidly fatal outcome. Scleroderma must be differentiated from many scleroderma-like conditions. Therapeutic problems are also discussed.

Adrenal Cortex Hormones↗
PubMedDate not supplied

Turkey muscle acylphosphatase: purification and comparative studies.

Turkey muscle acylphosphatase is strongly bound to anti-(horse muscle acylphosphatase ) antibodies covalently linked to an agarose resin. This permits use of an affinity chromatography step in the purification, which increased the final yield and allowed us to isolate three different molecular forms of the enzyme. Form 1 is a mixed disulfide between the polypeptide chain and glutathione; form 3 is an S-S dimer of the polypeptide chain present in form 1, while form 2, present in a very low amount, consists of a polypeptide chain quite similar in aminoacid composition to that found in form 1. The three molecular forms show very similar kinetic parameters. The comparison of these molecular forms with those isolated from horse muscle showed similar kinetic properties but different structural features.

Acid Anhydride Hydrolases↗