in this study, the effects of various concentrations of nacl and kcl and partial replacement of nacl withkcl on the growth characteristics of l. monocytogenes were evaluated. it was found that l. monocytogenescan grow in the presence of 1-9% nacl and 1-11% kcl. the higher the concentration of salt used, the longerthe lag phase induced. in addition, it was observed that l. monocytogenes tolerate...

conclusions l. innocua is not a pathogen, but the presence of the bacterium could be an indicator of probable contamination with l. monocytogenes. moreover, there is a potential risk to public health from the consumption of raw or undercooked burgers, which may increase the possibility of the acquisition of resistance to antibiotics. objectives the aim of this study was to evaluate the occurren...

The objective of this study was to isolation and characterization of Listeria species and determines Listeria monocytogenes serotypes in fresh fish, shrimp, crab and lobster in Isfahan and Shahrekord, Iran. From September 2010 to April 2011, a total of 300 samples of fresh fish, shrimp, crab and lobster were obtained from randomly selected retail stores in Isfahan and Shahreko...

Mitochondria are essential and highly dynamic organelles, constantly undergoing fusion and fission. We analyzed mitochondrial dynamics during infection with the human bacterial pathogen Listeria monocytogenes and show that this infection profoundly alters mitochondrial dynamics by causing transient mitochondrial network fragmentation. Mitochondrial fragmentation is specific to pathogenic Lister...

Listeria can escape host autophagy defense pathways through mechanisms that remain poorly understood. We show here that in epithelial cells, Listeriolysin (LLO)-dependent cytosolic escape of Listeria triggered a transient amino-acid starvation host response characterized by GCN2 phosphorylation, ATF3 induction and mTOR inhibition, the latter favouring a pro-autophagic cellular environment. Surp...

Subclinical infection of BALB/c mice with the intracellular bacterial pathogen Listeria monocytogenes results in the development of protective antilisterial immunity. L. monocytogenes can infect hepatocytes, and antilisterial cytotoxic T lymphocytes (CTL) lyse Listeria-infected hepatocytes in a major histocompatibility complex (MHC) class Ia-restricted manner. It remained to be determined wheth...

Infection of mice with the intracellular bacterium Listeria monocytogenes results in a strong CD8(+) T cell response that is critical for efficient control of infection. We used CD28-deficient mice to characterize the function of CD28 during Listeria infection, with a main emphasis on Listeria-specific CD8(+) T cells. Frequencies and effector functions of these T cells were determined using MHC...

Enhanced haemolysis agar (EHA) was compared to the two conventional Listeria isolation agars Oxford and PALCAM for its ability to detect Listeria spp. from production lines of fresh to cold-smoked fish. The ability of EHA for distinguishing L. monocytogenes colonies from other Listeria spp. was also evaluated.A total of 243 fish and environmental samples were analysed. Overall, 42 samples were ...

A multiplex polymerase chain reaction was developed to simultaneously identify Listeria monocytogenes and species of the genus Listeria. Two sets of primers were used, with the first amplifying a 938-bp region of the 16S rRNA gene that is highly conserved in all Listeria species and the second amplifying a 174-bp region of the listeriolysin (hlyA) gene of L. monocytogenes. Thus, isolates of Lis...

Listeriosis is a foodborne disease caused by Listeria monocytogenes and is considered as a serious health problem, due to the severity of symptoms and the high mortality rate. Recently, other Listeria species have been associated with disease in human and animals. The aim of this study was to develop a multiplex polymerase chain reaction (PCR) in order to simultaneously detect six Listeria spec...