Eremomycin--new glycopeptide antibiotic: chemical properties and structure.

Carboxamides and hydrazide of glycopeptide antibiotic eremomycin. Synthesis and antibacterial activity.

Carboxamides and hydrazide of glycopeptide antibiotic eremomycin were obtained by a direct reaction of the carboxy group of eremomycin with an appropriate amine or hydrazine using diphenyl phosphorazidate as a condencing agent. Eremomycin hydrazide was also obtained by hydrazinolysis of the eremomycin methyl ester. Use of dicyclohexylcarbodiimide or 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide...

New chiral stationary phase with macrocyclic glycopeptide antibiotic eremomycin chemically bonded to silica.

A new chiral stationary phase (CSP) was prepared by attachment of macrocyclic glycopeptide antibiotic eremomycin to the epoxy-activated silica under mild conditions. In contrast to CSP with immobilized vancomycin, which is a close structural analogue of eremomycin, the prepared CSP reveals high enantioselectivity for separation of amino acids enantiomers. It was demonstrated by the example of r...

Mm45289, a Potent Glycopeptide Antibiotic Which Interacts

MM45289 (A82846A, eremomycin), a glycopeptide antibiotic of the vancomycin type, was confirmed to have improved antibacterial activity over vancomycin. However its affinity (Ka) for the target site peptide mimetic diacetyl-L-lysyl-D-alanyl-D-alanine (DALAA)was 23-fold lower. Concentrations of DALAArequired to reverse the antibacterial activity of MM45289 were in the order of 10 to 50-fold highe...

Chemical modification of the eremomycin antibiotic. Formation of a cyclic covalent dimer.

Glycopeptide antibiotic resistance genes in glycopeptide-producing organisms.

The mechanism of high-level resistance to vancomycin in enterococci consists of the synthesis of peptidoglycan terminating in D-alanyl-D-lactate instead of the usual D-alanyl-D-alanine. This alternate cell wall biosynthesis pathway is ensured by the collective actions of three enzymes: VanH, VanA, and VanX. The origin of this resistance mechanism is unknown. We have cloned three genes encoding ...