It was previously shown that enhanced nisin resistance in some mutants was associated with increased expression of three genes, pbp2229, hpk1021, and lmo2487, encoding a penicillin-binding protein, a histidine kinase, and a protein of unknown function, respectively. In the present work, we determined the direct role of the three genes in nisin resistance. Interruption of pbp2229 and hpk1021 eli...

Examination of Bacillus subtilis strains containing multiple mutations affecting the class A high-molecular-weight penicillin-binding proteins (PBPs) 1, 2c, and 4 revealed a significant degree of redundancy in the functions of these three proteins. In rich media, loss of PBPs 2c and 4 resulted in no obvious phenotype. The slight growth and cell morphology defects associated with loss of PBP 1 w...

Listeria monocytogenes virulence depends on the activity of well-characterized virulence factors. In this study, transcription levels of inlA, inlB, hly, bsh and prfA genes in L. monocytogenes strains, and the ability of invasion into CaCo-2 cells were investigated. Serotyping, multiplex-PCR for serovar identification and restriction fragment analysis of inlA were performed. Transcription level...

We previously reassigned the amber UAG stop triplet as a sense codon in Escherichia coli by expressing a UAG-decoding tRNA and knocking out the prfA gene, encoding release factor 1. UAG triplets were left at the ends of about 300 genes in the genome. In the present study, we showed that the detrimental effect of UAG reassignment could be alleviated by increasing the efficiency of UAG translatio...

Listeria monocytogenes is a facultative intracellular foodborne pathogen responsible for listeriosis. In a recent study, in which we investigated neglected exogenous routes of transmission of foodborne pathogens into the European Union, we have isolated 15 L. monocytogenes strains in food products, which were imported from the Republic of Moldavia to Romania and illegally sold at a local market...

The aim of the present study was to assess transcription Listeria monocytogenes key virulence genes, namely sigB, prfA, hly, plcA, plcB, inlA, inlB, inlC and inlJ during subsistence on surface tomato, cucumber carrot stored at 4, 10 30 °C for 0, 0.5, 6 24 h. Gene relative assessed through reverse transcription-quantitative polymerase chain reaction (RT-qPCR). results obtained, indicated that pl...

Probabilistic finite automata (PFA) model stochastic languages, i.e. probability distributions over strings. Inferring PFA from stochastic data is an open field of research. We show that PFA are identifiable in the limit with probability one. Multiplicity automata (MA) is another device to represent stochastic languages. We show that a MA may generate a stochastic language that cannot be genera...

occipital neuralgia is a condition manifested by chronic occipital headaches and is thought to be caused by irritation or trauma to the greater occipital nerve (gon). treatment for occipital neuralgia includes medications, nerve blocks, and pulsed radiofrequency ablation (prfa). landmark-guided gon blocks are the mainstay in both the diagnosis and treatment of occipital neuralgia. ultrasound is...

This study aimed to evaluate the antimicrobial and antibiofilm activities of black pepper essential oil (BPEO) piperine effect on gene expression in a multispecies biofilm composed Listeria monocytogenes, Salmonella Typhimurium, Pseudomonas aeruginosa polypropylene surface. The minimal inhibitory concentrations BPEO were 100 25 mg/mL, respectively, against this consortium microorganisms. Sessil...