Arthrichitin. A New Cell Wall Active Metabolite from Arthrinium phaeospermum.

Arthrichitin (1), C(33)H(46)N(4)O(9), is a new cell wall active depsipeptide isolated from the fermentation broth of Arthrinium phaeospermum (HIL Y-903022). Its structure was elucidated on the basis of spectroscopic and chemical degradation studies. Arthrichitin consists of serine, beta-keto tryptophan, glutamic acid, and 2,4-dimethyl-3-hydroxydodecanoic acid units.

Improved screening for beta-lactam antibiotics. A sensitive, high-throughput assay using DD-carboxypeptidase and a novel chromophore-labeled substrate.

The very sensitive and specific method for the detection of beta-lactam antibiotics using DD-carboxypeptidase (DDCase) from Actinomadura strain R39 has been improved to meet the requirements of a high-throughput beta-lactam screening from culture broths of microorganisms. The method is based on a novel chromophor-labeled substrate N alpha-acetyl-N epsilon-4-(7-nitrobenzofurazanyl)-L-lysyl-D-al anyl-D-alanine (ANLA2) which is converted by DDCase into ANLA1 with only one D-alanine residue left. Both compounds are intensely yellow as well as highly fluorescent and can be separated by thin-layer chromatography. This allows easy determination of residual DDCase activity after reaction with beta-lactams by simple visual inspection of chromatograms. Also, many assays can be run at a time without sophisticated instrumentation. Details of the method as well as some results of a beta-lactam screening performed with this type of assay are described.

Swalpamycin, a new macrolide antibiotic. I. Taxonomy of the producing organism, fermentation, isolation and biological activity.

A new macrolide antibiotic, swalpamycin, has been isolated from the culture broth of Streptomyces sp. Y-84,30967. Taxonomically the producing organism most closely resembles Streptomyces anandii and has therefore been named S. anandii subsp. swalpus. Swalpamycin is a neutral 16-membered macrolide active against Gram-positive bacteria including erythromycin-resistant strains.

Butalactin, a new butanolide antibiotic. Taxonomy, fermentation, isolation and biological activity.

Butalactin, [2-(4',5'-epoxy-hex-2'(E)-en)oyl-2-hydroxy-3-hydroxymethyl-2, 3-(Z)-butanolide] is a new antibiotic produced by Streptomyces sp. HIL Y-86,36923. Taxonomically, the producing organism most closely resembles Streptomyces corchorusii. The strain also produces cineromycin B. Though butalactin is structurally related to 'signal molecules' such as A-factor, the anthracycline inducing factors and the virginiae butanolides, it does not show inducing activity for antibiotic production or aerial mycelium formation in the indicator strain. Butalactin possesses a weak antibiotic activity against Gram-positive and Gram-negative bacteria.

Alisamycin, a new antibiotic of the manumycin group. I. Taxonomy, production, isolation and biological activity.

Alisamycin is a new member of the manumycin group of antibiotics produced by Streptomyces sp. HIL Y-88,31582, which taxonomically appears to be Streptomyces actuosus. Alisamycin is active against Gram-positive bacteria and fungi, and has a weak antitumour activity.

Mulundocandin, a new lipopeptide antibiotic. I. Taxonomy, fermentation, isolation and characterization.

Mulundocandin, a new lipopeptide antibiotic, was isolated from the culture broth of a strain of Aspergillus sydowi No. Y-30462. The antibiotic, obtained as a colorless amorphous powder having the molecular formula C48H77N7O16, is an antifungal antibiotic active against yeasts and filamentous fungi.

Mulundocandin, a new lipopeptide antibiotic. II. Structure elucidation.

The structure of a new antifungal antibiotic, mulundocandin, C48H77N7O16, was elucidated by high field NMR experiments e.g., homo- and heteronuclear correlation spectra, distortionless enhancement by polarization transfer (DEPT) spectra as well as nuclear Overhauser effect. The compound is a lipopeptide antibiotic belonging to the echinocandin class.

Aranorosin, a novel antibiotic from Pseudoarachniotus roseus. I. Taxonomy, fermentation, isolation, chemical and biological properties.

A novel antibiotic, aranorosin, was isolated from the fermentation broth of a new fungal isolate identified as Pseudoarachniotus roseus. The antibiotic showed a wide spectrum of activity.

Balhimycin, a new glycopeptide antibiotic produced by Amycolatopsis sp. Y-86,21022. Taxonomy, production, isolation and biological activity.

A new glycopeptide antibiotic, balhimycin, has been isolated from the fermentation broth of a Amycolatopsis sp. Y-86,21022. Balhimycin belongs to the vancomycin class of glycopeptides and contains a dehydrovancosamine sugar. The biological activity of balhimycin has been compared extensively with that of vancomycin against methicillin resistant staphylococci and also against anaerobes. Balhimycin is marginally superior to vancomycin in its in vitro activity against anaerobes and in its bactericidal properties.

Aranorosin, a novel antibiotic from Pseudoarachniotus roseus. II. Structure elucidation.

Aranorosin, a new antifungal antibiotic, has been isolated from the culture filtrate and mycelium of a strain of Pseudoarachniotus roseus Kuehn. The antibiotic, C23H33NO6, contains a novel 1-oxaspiro[4,5]decane ring system. The structure (I) has been elucidated on the basis of spectroscopic and chemical analysis.

Swalpamycin, a new macrolide antibiotic. II. Structure elucidation.

A new antibiotic swalpamycin (1) has been isolated from the culture broth of Streptomyces sp. Y-84,30967. The antibiotic has the molecular formula of C37H56O14 and belongs to the class of 16-membered neutral macrolide antibiotics. Its structure has been elucidated by an analysis of its spectral properties. It contains a novel aglycone herein called swalpanolide.

Deoxymulundocandin--a new echinocandin type antifungal antibiotic.

A new echinocandin type antifungal antibiotic, deoxymulundocandin, C48H77N7O15, was isolated from the culture filtrate and mycelia of a fungal culture, Aspergillus sydowii (Bainier and Sartory) Thom and Church var. nov. mulundensis Roy (Culture No. Y-30462). The structure was established by comparative GC-MS analyses of the derivatized acid hydrolysates of deoxymulundocandin and mulundocandin as well as by the high field NMR experiments (COSY, NOESY and DEPT).

Aranorosinol A and aranorosinol B, two new metabolites from Pseudoarachniotus roseus: production, isolation, structure elucidation and biological properties.

Two new secondary metabolites, aranorosinol A (1) and aranorosinol B (2), were isolated from a strain of Pseudoarachniotus roseus. Their structures were elucidated on the basis of their spectral properties and chemical transformations and were found to be similar to aranorosin (3) isolated from the same strain.

Mersacidin, a new antibiotic from Bacillus. Fermentation, isolation, purification and chemical characterization.

Mersacidin (1) is a new peptide antibiotic containing beta-methyllanthionine. It is classified as a member of the proposed lantibiotic group of antibiotics, and is produced by a species of Bacillus. Mersacidin has a molecular weight of 1,824 (C80H120N20O21S4). The antibiotic is active against Gram-positive organisms including methicillin-resistant Staphylococcus aureus, but has no activity against Gram-negative bacteria or fungi.

Mersacidin, a new antibiotic from Bacillus. In vitro and in vivo antibacterial activity.

Mersacidin is a new peptide antibiotic of the proposed lantibiotic family. It is active in vitro and in vivo against Gram-positive bacteria including the methicillin-resistant Staphylococci. Its in vitro activity is less than those of vancomycin and erythromycin but it shows much higher activity in the in vivo system than can be expected from the in vitro testing results. A water soluble potassium salt has been prepared which has an activity profile similar to that of mersacidin, but has better in vivo activity against Streptococcus pyogenes than the parent compound.

Stereochemistry of the epoxydon group antibiotic G7063-2 isolated from a Streptomyces species HPL Y-25711.

The absolute configuration of the ring system of the antibiotic G7063-2 has been established as being the same as that reported for terreic acid, based on circular dichroism data. During structure elucidation experiments, reaction with ethereal diazomethane gave an adduct whose structure is proposed.