Investigation of the complex antibiotic INA-5812

A concentrate with the antimicrobial activity has been isolated from the culture broth of Streptomyces roseoflavus INA-Ac-5812. Its further fractionation by reversed-phase HPLC has resulted in six fractions. It has been established by MALDI-TOF and ESI-MSn precision mass-spectrometry methods that the main components of the complex antibiotic are several closely related compounds, presumably of a glycopeptide nature. The fraction containing an individual component with a mass of 1845.788 Da has been characterized by UV/Vis absorbance and fluorescence spectra, amino acid analysis, and derivatization with tris(2,6-dimethoxyphenyl)methyl cation. The activity of fractions against pathogenic microbes has been studied. The results allow the supposition that the INA-5812 antibiotic complex is a glyco- or lipoglycopeptide antibiotic of a new type, which is very promising for further study. © 2016, Pleiades Publishing, Ltd

Investigation of the complex antibiotic INA-5812

A concentrate with the antimicrobial activity has been isolated from the culture broth of Streptomyces roseoflavus INA-Ac-5812. Its further fractionation by reversed-phase HPLC has resulted in six fractions. It has been established by MALDI-TOF and ESI-MSn precision mass-spectrometry methods that the main components of the complex antibiotic are several closely related compounds, presumably of a glycopeptide nature. The fraction containing an individual component with a mass of 1845.788 Da has been characterized by UV/Vis absorbance and fluorescence spectra, amino acid analysis, and derivatization with tris(2,6-dimethoxyphenyl)methyl cation. The activity of fractions against pathogenic microbes has been studied. The results allow the supposition that the INA-5812 antibiotic complex is a glyco- or lipoglycopeptide antibiotic of a new type, which is very promising for further study. © 2016, Pleiades Publishing, Ltd

A revised B(E2;2

The lifetimes of the $2^+_1$ , the $2^+_2$ and the $3^-_1$ states of 210Po have been measured in the 208Pb(12C,10Be)210Po transfer reaction by the Doppler-shift attenuation method. The result for the lifetime of the $2^+_1$ state is about three times shorter than the adopted value. However, the new value still does not allow for a consistent description of the properties of the yrast $2^+_1$ , $4^+_1$ , $6^+_1$ , and $8^+_1$ states of 210Po in the framework of nuclear shell models. Quasi-particle Phonon Model (QPM) calculations also cannot overcome this problem thus indicating the existence of a peculiarity which is neglected in both theoretical approaches