Peptidoglycan hydrolase enterolysin a recognizes lipoteichoic acid chains in the cell walls of sensitive bacteria.

C-terminal domain of peptidoglycan hydrolase enterolysin A (EnlA) is involved in specific recognition and binding to the target cell envelopes and represents true cell wall binding (CWB) domain. Sensitivity/resistance to EnlA is dependent on binding ability/disability of its CWB domain. We assume that main mechanism of resistance against EnlA is absence of the specific receptor on the cell surface, which is necessary for binding of the enzyme molecule. Using competitive and enzymatic assays we have uncovered the chemical nature of the EnlA receptor, which is a lipoteichoic acid.

The occurrence and rapid discrimination of Fomes fomentarius genotypes by ITS-RFLP analysis.

Sequence comparison of available Fomes fomentarius (L.) J. Kickx f. internal transcribed spacer (ITS) of ribosomal DNA sequences demonstrated genetic non-homogeneity of the species. Multiple sequence alignment indicated the presence of two genotypes with overall similarity of about 97% and a strong statistics support. Rapid and reliable method for discrimination of F. fomentarius genotypes based on restriction digestion of polymerase chain reaction (PCR)-amplified ITS sequences was developed. BseNI and SchI restriction endonucleases were found to clearly discriminate between two F. fomentarius genotypes. The method was used to study the variability in F. fomentarius isolates collected from natural forest reserves in Vihorlat Mountains (East Slovakia). In most localities both genotypes occur concurrently. The isolates belonging to the genotype A were found to be prevalent on beech (Fagus sylvatica), while genotype B tends to be found mainly on other hosts. The grouping of selected isolates was confirmed by sequence analysis. Our results indicate that F. fomentarius includes at least two sympatric cryptic species.