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C Coronelli

Publications and source records attributed to C Coronelli.

At least 19 recordsLinked to original sources

Teicoplanin: chemical, physico-chemical and biological aspects.

The structure determination and the physico-chemical properties of teicoplanin, a new glycopeptide antibiotic of the vancomycin-ristocetin family are presented. Some biological studies and the mechanism of action at the molecular level are discussed. Analytical test methods, such as HPLC assay, bioassay and enzymatic assay are described. The antimicrobial activity of teicoplanin and of some relevant acid and basic hydrolysis products are also discussed.

Animals

Teichomycins, new antibiotics from Actinoplanes teichomyceticus nov. sp. IV. Separation and characterization of the components of teichomycin (teicoplanin).

Teichomycin (teicoplanin) was found to be a mixture of five closely related components of similar polarity, designated T-A2-1, 2, 3, 4 and 5 and of one more polar component, designated T-A3. The separation of the single components was achieved by reverse phase partition chromatography and their physico-chemical and biological properties were compared. The results show that 1) the five major components have the same molecular size of about 1,900; 2) they contain the same ionization function, i.e., a carboxyl group and an amino group which form a zwitterion, and four phenolic groups; 3) they differ in a side aliphatic chain. The component T-A3 is not described.

Actinomycetales

Teicoplanin, antibiotics from Actinoplanes teichomyceticus nov. sp. V. Aromatic constituents.

Oxidative and hydrolytic degradation reactions were carried out on teicoplanin in order to characterize the aromatic portion of the molecule and relate it to the other members of the class of glycopeptide antibiotics. Seven aromatic rings, obtained as triphenyl ether, diphenyl ether, and diphenyl moieties after oxidation nd hydrolysis of teicoplanin, were identified. They are present in teicoplanin as aromatic amino acids and constitute the peptidic part of the molecule. The diphenyl ether and diphenyl moieties, which were isolated both as esters after oxidation and as alpha-amino acids after acid hydrolysis clearly indicate the nature of the corresponding amino acids in teicoplanin. The triphenyl ether moiety, which was isolated only as ester, allows the hypothesis that the corresponding amino acids are the same as those of the other glycopeptide antibiotics.

Actinomycetales

Teichomycins, new antibiotics from Actinoplanes teichomyceticus nov. sp. II. Extraction and chemical characterization.

The teichomycins are new antibiotics produced by Actinoplanes teichomyceticus nov. sp. Teichomycin A1 is a phosphorus-containing antibiotic, active in vitro and in vivo against gram-positive bacteria, and active only in vitro against gram-negative bacteria. Teichomycin A2 is a chlorine-containing antibiotic, active in vitro and in vivo against gram-positive bacteria. Isolation, purification and physical and chemical properties of the two antibiotics are reported. Teichomycin A1 is a member of the phosphoglycolipid class of antibiotics while teichomycin A2 is related to the group of the glycopeptide antibiotics.

Actinomycetales

Gardimycin, a new antibiotic from Actinoplanes. II. Isolation and preliminary characterization.

The strain Actinoplanes garbadinensis nov. sp. produces a peptide antibiotic, named gardimycin, which is active in vitro and in vivo against Gram-positive bacteria. Isolation and purification of the product have been accomplished by extraction from the broth with butanol and dialysis of the crude extract, followed by counter-current distribution. Gardimycin is an open chain peptide with an approximate minimal formula C84H138N18S3-4O34Na. The following amino acids have been identified by column chromatography of an acid hydrolysate: serine, glutamic acid, alanine, leucine, isoleucine, glycine, valine and two sulphur-containing amino acids whose structure is presently under study. Tryptophan has been identified in an alkaline hydrolysate.

Actinomycetales

Lipiarmycin, a new antibiotic from Actinoplanes. II. Isolation, chemical, biological and biochemical characterization.

Lipiarmycin, a metabolite of Actinoplanes deccanensis nov. sp. (PARENTI et al.), has been isolated in pure form. It has a molecular formula C52 CONGRUENT TO 54H74 CONGRUENT TO 76Cl2O19, (M.W. = 1,073 CONGRUENT TO 1,099). From its chemical and physico-chemical characteristics, lipiarmycin can be considered a new antibiotic. Lipiarmycin is highly active against Gram-positive bacteria, including strains resistant to the medically important antibiotics and protects mice experimentally infected with Streptococcus haemolyticus. Liparmycin inhibits growth of susceptible bacteria by interfering with RNA synthesis.

Animals