ABSTRACT
Peptide antibiotic with cyanolytic activity was isolated from the IGM52 strain of the Brevibacillus laterosporus Gram-positive spore-forming bacteria. By 1H NMR spectroscopy, this antibiotic was identified as loloatin A, a cyclic decapeptide cyclo(-Asn-Asp-Tyr-Val-Orn-Leu-DTyr-Pro-Phe-DPhe-). The spatial structure of loloatin A in solution was determined. The English version of the paper: Russian Journal of Bioorganic Chemistry, 2002, vol. 28, no. 4; see also http://www.maik.ru.
Subject(s)
Anti-Bacterial Agents/isolation & purification , Bacillus/chemistry , Peptides, Cyclic/isolation & purification , Amino Acid Sequence , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Cyanobacteria/drug effects , Magnetic Resonance Spectroscopy , Models, Molecular , Peptides, Cyclic/chemistry , Peptides, Cyclic/pharmacology , Protein ConformationABSTRACT
The lysogeny of eleven type strains of Bacillus thuringiensis was studied. Eight new phages were isolated from the variants B. thuringiensis var. tochigiensis, yunnanensis, colmeri, shandongiensis, neoleonensis, silo, mexicanensis, and toguchini belonging to the B1 morphotype. The phages that were isolated from B. thuringiensis var. tochigiensis, yunnanensis, shandongiensis, and mexicanensis possessed transverse disks at their tails and were classified into one morphological group. The protein patterns of the isolated phages were determined.
Subject(s)
Bacillus thuringiensis/virology , Bacteriophages/ultrastructure , Lysogeny , Viral Proteins/analysis , Bacteriophages/isolation & purification , Molecular Weight , Species SpecificityABSTRACT
A new bacteriophage Tt91 of larger size and broad lytical spectrum has been isolated from soil to widen the possibility to study new Bacillus thuringiensis strains. The Tt91 bacteriophage was shown to perform the intravariant transduction and, thus, can be used for genetic mapping. The ultrastructural analysis made it possible to refer bacteriophage Tt91 to morphotype A1 and showed similarity of Tt91 morphological structure to the one of CP-group bacteriophages. The performed comparative analysis of phage-specific proteins has confirmed a possible relation of the bacteriophages and revealed the differences between them. The data on the resistance of Tt91 DNA to majority of site-specific restriction endonucleases (17 out of 18 tested) and on DNA melting in the wide interval of temperatures suggests the presence of possible anomalies in the Tt91 DNA.
