Structural and functional properties of antimicrobial protein L5 of Lysоbacter sp. XL1.

The Gram-negative bacterium Lysobacter sp. XL1 secretes into the extracellular space five bacteriolytic enzymes that lyse the cell walls of competing microorganisms. Of special interest are homologous lytic proteases L1 and L5.

Rathayibacter oskolensis sp. nov., a novel actinobacterium from Androsace koso-poljanskii Ovcz. (Primulaceae) endemic to the Central Russian Upland.

A rod-shaped, non-endospore-forming and non-motile bacterium, strain DL-329, was isolated from the above-ground part of a plant, Androsace koso-poljanskii Ovcz. (Primulaceae), at the the State Natural Reserve 'Belogorie', Russia. On the basis of 16S rRNA gene sequence comparisons, the strain clustered with members of the genus Rathayibacter, showing the highest sequence similarity to Rathayibacter tritici (98.

Two novel thermally resistant endolysins encoded by pseudo T-even bacteriophages RB43 and RB49.

Identification and cloning of genes as well as biochemical characterization of the gene products were carried out for two novel endolysins of pseudo T-even lytic bacteriophages RB43 and RB49, which represent different myovirus groups of the subfamily . Genes RB43ORF159c and RB49р102 were cloned in cells, and their products were purified to electrophoretic homogeneity with an up to 80 % yield of total activity. In respect to substrate specificity, both enzymes were found to be lytic l-alanoyl-d-glutamate peptidases belonging to the M15 family.

Identification and characterization of the metal ion-dependent L-alanoyl-D-glutamate peptidase encoded by bacteriophage T5.

Although bacteriophage T5 is known to have lytic proteins for cell wall hydrolysis and phage progeny escape, their activities are still unknown. This is the first report on the cloning, expression and biochemical characterization of a bacteriophage T5 lytic hydrolase. The endolysin-encoding lys gene of virulent coliphage T5 was cloned in Escherichia coli cells, and an electrophoretically homogeneous product of this gene was obtained with a high yield (78% of total activity).

Substrate specificity and some physicochemical properties of autolytic enzymes of the bacterium Lysobacter sp. XL 1.

The substrate specificity of autolytic enzymes of the bacterium Lysobacter sp. XL 1 has been established. The periplasmic enzyme A8, the cytosolic enzyme A1, and the enzyme A10 solubilized from the cell walls and membranes with Triton X-100 exhibit glucosaminidase activity; the cytosolic enzyme A4 and the enzyme A9 solubilized from the cell walls and membranes with LiCl exhibit the muramidase activity.

Specificity of the action of lysoamidase on Staphylococcus aureus 209P cell walls.

Specificity of Staphylococcus aureus 209P cell wall hydrolysis by the L1 and L2-bacteriolytic enzymes from lysoamidase lytic complex was studied. L1-peptidase was shown to display both glycyl-glycine endopeptidase and N-acetylmuramyl-L-alanine amidase enzymatic activities on the S. aureus peptidoglycan molecule, whereas L2-peptidase acts as N-acetylmuramyl-L-alanine amidase.