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Infection and Immunity Dec 1989The strong bizonal hemolysis on blood agar and the positive CAMP reaction with Rhodococcus equi denotes the production of two different cytolytic factors by Listeria...
The strong bizonal hemolysis on blood agar and the positive CAMP reaction with Rhodococcus equi denotes the production of two different cytolytic factors by Listeria ivanovii. One was characterized as a thiol-activated (SH) cytolysin of 61 kilodaltons and was termed ivanolysin O (ILO) since data suggested that it is different from listeriolysin O, the SH-cytolysin produced by Listeria monocytogenes. The other is a 27-kilodalton hemolytic sphingomyelinase C that was found to be the cytolytic factor responsible for the halo of incomplete hemolysis synergistically enhanced by R. equi exosubstances. When thiol-disulfide exchange affinity chromatography and gel filtration were applied to the purification of ILO from concentrated L. ivanovii culture supernatants, the copurification of the two cytolysins was observed. This phenomenon seems to be due to the formation of intermolecular disulfide bonds between ILO and the sphingomyelinase, since the latter was found to contain free SH groups, not essential for the activity. These SH groups could react with the single cysteine residue characteristically present in the SH-cytolysins, forming a dimeric cytolytic complex. The purification of ILO was achieved by a further gel filtration with a reducing agent (dithiothreitol) in the eluent. A method for the purification of the sphingomyelinase based on selective sequestration of ILO from the L. ivanovii concentrated culture supernatant by the SH cytolysin target molecule cholesterol and thiol-disulfide affinity chromatography is described.
Topics: Bacterial Toxins; Blotting, Western; Cholesterol; Cytotoxins; Listeria; Molecular Weight; Phosphoric Diester Hydrolases; Sphingomyelin Phosphodiesterase; Sulfhydryl Compounds
PubMed: 2553614
DOI: 10.1128/iai.57.12.3928-3935.1989 -
TheScientificWorldJournal 2012The present study was carried out to investigate the potential of Listeria ivanovii isolates to exist as biofilm structures. The ability of Listeria ivanovii isolates to...
The present study was carried out to investigate the potential of Listeria ivanovii isolates to exist as biofilm structures. The ability of Listeria ivanovii isolates to adhere to a surface was determined using a microtiter plate adherence assay whereas the role of cell surface properties in biofilm formation was assessed using the coaggregation and autoaggregation assays. Seven reference bacterial strains were used for the coaggregation assay. The degree of coaggregation and autoaggregation was determined. The architecture of the biofilms was examined under SEM. A total of 44 (88%) strains adhered to the wells of the microtiter plate while 6 (12%) did not adhere. The coaggregation index ranged from 12 to 77% while the autoaggregation index varied from 11 to 55%. The partner strains of S. aureus, S. pyogenes, P. shigelloides, and S. sonnei displayed coaggregation indices of 75% each, while S. Typhimurium, A. hydrophila, and P. aeruginosa registered coaggregation indices of 67%, 58%, and 50%, respectively. The ability of L. ivanovii isolates to form single and multispecies biofilms at 25°C is of great concern to the food industry where these organisms may adhere to kitchen utensils and other environments leading to cross-contamination of food processed in these areas.
Topics: Bacterial Adhesion; Biofilms; Food Contamination; Food Microbiology; Listeria; Microscopy, Electron, Scanning; Pseudomonas aeruginosa; South Africa; Staphylococcus aureus
PubMed: 23365535
DOI: 10.1100/2012/873909 -
Emerging Microbes & Infections Jun 2017Listeria is ubiquitous in a variety of environments and can be isolated from a wide range of animal hosts. Rodents are capable of carrying pathogenic bacteria in their...
Listeria is ubiquitous in a variety of environments and can be isolated from a wide range of animal hosts. Rodents are capable of carrying pathogenic bacteria in their intestines, such as Listeria, and can disseminate those pathogens into the natural environment and to where human activity occurs. In this study, we investigated the occurrence and antimicrobial susceptibility of Listeria spp. isolated from wild rodents found in natural environments in China. We collected 341 intestinal fecal samples of rodents from five different regions of China, all representing different rodent habitats. The antimicrobial susceptibility of the Listeria spp. isolates obtained were firstly assessed using the Kirby-Bauer disk diffusion method. Thirty-one samples were positive for Listeria spp., of which 11 were positive for Listeria monocytogenes and seven were positive for Listeria ivanovii. Other species identified include Listeria innocua, Listeria fleischmannii and Listeria floridensis. All Listeria spp. isolates were sensitive to the majority of the antimicrobials tested, but largely resistant to oxacillin (94.1%) and cefuroxime (70.6%). All L. monocytogenes isolates were further characterized by serotyping, multi-locus sequence typing (MLST) and pulsed-field gel electrophoresis (PFGE). L. monocytogenes strains were grouped into three serotypes, five sequence types and five pulsotypes (PTs) by serotyping, MLST and PFGE, respectively. Almost half of the isolates (five of 11) belonged to serotype 1/2b, ST87 and PT1. This study determined that Listeria is carried in the intestinal tracts of wild rodents from multiple regions at a low rate, filling an epidemiological data gap on Listeria in natural environments in China.
Topics: Animals; Anti-Bacterial Agents; China; Disease Reservoirs; Drug Resistance, Multiple, Bacterial; Electrophoresis, Gel, Pulsed-Field; Feces; Genotype; Listeria; Listeria monocytogenes; Listeriosis; Multilocus Sequence Typing; Rodentia; Serotyping
PubMed: 28588285
DOI: 10.1038/emi.2017.28 -
International Journal of... 2007Among Listeria genus, only two species, Listeria ivanovii and Listeria monocytogenes, are pathogenic. L. ivanovii is almost only associated with infections in animals,...
Among Listeria genus, only two species, Listeria ivanovii and Listeria monocytogenes, are pathogenic. L. ivanovii is almost only associated with infections in animals, mainly sheep and cattle, and has rarely been associated with human infections, whereas L. monocytogenes causes severe illnesses in both humans and animals. To further investigate the pathogenetic features of L. ivanovii in humans, we undertook a study in which the intracellular behaviour of this pathogen was analysed in WISH cells, a cell line derived from human amniotic tissue, and compared to that of L. monocytogenes. Using microbiological, biochemical, and ultrastructural approaches, we demonstrate that L. ivanovii can adhere to and invade human amniotic cells, lyse the phagosomal membrane, polymerize host cell actin, and spread from cell to cell more efficiently than L. monocytogenes. However, although L. ivanovii is capable of specifically infecting and replicating in human amnion cells, its survival in cytoplasm is limited compared to that of L. monocytogenes.
Topics: Amnion; Bacterial Adhesion; Cell Line; Cytoplasm; Female; Humans; Listeria; Microscopy, Electron, Transmission
PubMed: 17880764
DOI: 10.1177/039463200702000309 -
FEMS Microbiology Letters Jan 1989In culture supernatants of both Listeria ivanovii and Listeria monocytogenes Sv4b, for the first time a hemolysin of molecular weight 58 kDa was identified, which had...
In culture supernatants of both Listeria ivanovii and Listeria monocytogenes Sv4b, for the first time a hemolysin of molecular weight 58 kDa was identified, which had all the characteristics of an SH-activated cytolysin, and which was therefore identified as listeriolysin O (LLO). In the case of L. ivanovii a second major supernatant protein of molecular weight 24 kDa co-purified with LLO. However, the function of this protein has to be determined. In culture supernatants of L. ivanovii a sphingomyelinase and a lecithinase activity could be detected, both enzymatic activities together contributing to the pronounced hemolysis caused by L. ivanovii. The N-terminal amino acid sequences of LLO and the 24 kDa from L. ivanovii are shown.
Topics: Amino Acid Sequence; Bacterial Toxins; Heat-Shock Proteins; Hemolysin Proteins; Listeria; Listeria monocytogenes; Molecular Sequence Data; Molecular Weight; Virulence
PubMed: 2498153
DOI: 10.1111/j.1574-6968.1989.tb03298.x -
Molecular Microbiology Aug 1999The ruminant pathogen Listeria ivanovii differs from Listeria monocytogenes in that it causes strong, bizonal haemolysis and a characteristic shovel-shaped co-operative...
The ruminant pathogen Listeria ivanovii differs from Listeria monocytogenes in that it causes strong, bizonal haemolysis and a characteristic shovel-shaped co-operative haemolytic ('CAMP-like') reaction with Rhodococcus equi. We cloned the gene responsible for the differential haemolytic properties of L. ivanovii, smcL. It encodes a sphingomyelinase C (SMase) highly similar (> 50% identity) to the SMases from Staphylococcus aureus (beta-toxin), Bacillus cereus and Leptospira interrogans. smcL was transcribed monocistronically and was expressed independently of PrfA. Low-stringency Southern blots demonstrated that, within the genus Listeria, smcL was present only in L. ivanovii. We constructed an smcL knock-out mutant. Its phenotype on blood agar was identical to that of L. monocytogenes (i.e. weak haemolysis and no shovel-shaped CAMP-like reaction with R. equi ). This mutant was less virulent for mice, and its intracellular proliferation was impaired in the bovine epithelial-like cell line MDBK. The role of SmcL in intracellular survival was investigated using an L. monocytogenes mutant lacking the membrane-damaging determinants hly, plcA and plcB, being thus unable to grow intracellularly. Complementation of this mutant with smcL on a plasmid was sufficient to promote bacterial intracellular proliferation in MDBK cells. Transmission electron microscopy showed that SmcL mediates the disruption of the phagocytic vacuole and the release of bacteria into the cytosol. Therefore, L. ivanovii possesses a third phospholipase with membrane-damaging activity that, together with PlcA and PlcB, may act in concert with the pore-forming toxin Hly to mediate efficient escape from the vacuolar compartment. The 5' end of smcL is contiguous with the internalin locus i-inlFE, which is also specific to L. ivanovii and is required for full virulence in mice. Thus, smcL forms part of a novel virulence gene cluster in Listeria that is species specific.
Topics: Amino Acid Sequence; Animals; Bacterial Proteins; Cattle; Cell Division; Cell Line; Cloning, Molecular; Gene Expression Regulation, Bacterial; Hemolysis; Listeria; Mice; Microscopy, Electron; Molecular Sequence Data; Mutation; Peptide Termination Factors; Phagocytosis; Phylogeny; RNA, Messenger; Sequence Alignment; Sphingomyelin Phosphodiesterase; Trans-Activators; Virulence
PubMed: 10417642
DOI: 10.1046/j.1365-2958.1999.01486.x -
Antibiotics (Basel, Switzerland) Dec 2020Native egg albumin (NEA) was isolated from hen eggs and hydrolyzed by pepsin to produce hydrolyzed egg albumin (HEA). HEA was chemically characterized and screened for...
Native egg albumin (NEA) was isolated from hen eggs and hydrolyzed by pepsin to produce hydrolyzed egg albumin (HEA). HEA was chemically characterized and screened for its antibacterial activity against 10 pathogenic bacteria (6 Gram (+) and 4 Gram (-)). The SDS-PAGE pattern of NEA showed molecular weights of hen egg albumin subunits ranging from 30 to 180 kDa. The highest intensive bands appeared at a molecular mass of about 50 and 97 kDa. Ultra-performance liquid chromatography (UPLC) of the peptic HEA revealed 44 peptides, 17 of them were dipeptides, and the other 27 fractions corresponded to bigger peptides (3-9 amino acids). The dipeptides and big peptides represented 26% and 74% of the total hydrolysate, respectively. The MIC of HEA was about 100 μg/L for , , , , , and and 150 μg/L for , , and and 200 μg/L for was the most sensitive organism to HEA. Mixtures of HEA with antibiotics showed more significant antibacterial activity than individually using them. Transmission electron microscopy (TEM) revealed various signs of cellular deformation in the protein-treated bacteria. HEA may electrostatically and hydrophobically interact with the cell wall and cell membrane of the susceptible bacteria, engendering large pores and pore channels leading to cell wall and cell membrane disintegration. Higher cell permeability may, thus, occur, leading to cell emptiness, lysis, and finally death. Alternatively, no toxicity signs appeared when HEA was administrated to Wistar Albino rats as one single dose (2000, 5000 mg/kg body weight) or repeated daily dose (500 and 2500 mg/kg body weight/day) for 28 days to disclose the possible toxicity hazards. HEA did not produce any death.
PubMed: 33322196
DOI: 10.3390/antibiotics9120901 -
Molecular Microbiology Jan 2006Listeria ivanovii differs from the human pathogen Listeria monocytogenes in that it specifically affects ruminants, causing septicaemia and abortion but not...
Listeria ivanovii differs from the human pathogen Listeria monocytogenes in that it specifically affects ruminants, causing septicaemia and abortion but not meningo-encephalitis. The genetic characterization of spontaneous L. ivanovii mutants lacking the virulence factor SmcL (sphingomyelinase) led us to identify LIPI-2, the first species-specific pathogenicity island from Listeria. Besides SmcL, this 22 kb chromosomal locus encodes 10 internalin (Inl) proteins: i-InlB1 and -B2 are large/surface-associated Inls similar to L. monocytogenes InlB; i-InlE to -L are small/excreted (SE)-Inls, i-InlG being a tandem fusion of two SE-Inls. Except i-inlB1, all LIPI-2 inl genes are controlled by the virulence regulator, PrfA. LIPI-2 is inserted into a tRNA locus and is unstable - half of it deleting at approximately 10(-4) frequency with a portion of contiguous DNA. The spontaneous mutants were attenuated in vivo in mice and lambs and showed impaired intracellular growth and apoptosis induction in bovine MDBK cells. Targeted knock-out mutations associated the virulence defect with LIPI-2 genes. The region between the core genome loci ysnB-tRNA(arg) and ydeI flanking LIPI-2 contained different gene complements in the different Listeria spp. and even serovars of L. monocytogenes, including remnants of the PSA bacteriophage int gene in serovar 4b, indicating it is a hot spot for horizontal genome diversification. LIPI-2 is conserved in L. ivanovii ssp. ivanovii and londoniensis, suggesting an early acquisition during the species' evolution. LIPI-2 is likely to play an important role in the pathogenic and host tropism of L. ivanovii.
Topics: Bacterial Proteins; Base Sequence; Chromosome Mapping; Gene Deletion; Genes, Bacterial; Genome, Bacterial; Listeria; Sphingomyelin Phosphodiesterase; Virulence
PubMed: 16390439
DOI: 10.1111/j.1365-2958.2005.04955.x -
International Journal of Molecular... Apr 2022causes infectious diseases in animals and is considered an emerging zoonotic pathogen involved in human clinical conditions. In silico analysis of plasmid pLG50 of...
causes infectious diseases in animals and is considered an emerging zoonotic pathogen involved in human clinical conditions. In silico analysis of plasmid pLG50 of Lg-Granada, an isolate from a patient with endocarditis, revealed the presence of two gene clusters (46-47 and 48-49), each one encoding a novel putative bacteriocin, i.e., garvicin AG1 (GarAG1; 46) and garvicin AG2 (GarAG2; 48), and their corresponding immunity proteins (47 and 49). The chemically synthesised bacteriocins GarAG1 and GarAG2 presented inhibitory activity against pathogenic strains, with AG2 also being active against , and . Genetic organisation, amino acid sequences and antimicrobial activities of GarAG1 and GarAG2 indicate that they belong to linear non-pediocin-like one-peptide class IId bacteriocins. Gram-positive bacteria that were sensitive to GarAG2 were also able to ferment mannose, suggesting that this bacteriocin could use the mannose phosphotransferase transport system (Man-PTS) involved in mannose uptake as a receptor in sensitive strains. Intriguingly, GarAG1 and GarAG2 were highly active against their own host, Lg-Granada, which could be envisaged as a new strategy to combat pathogens via their own weapons.
Topics: Animals; Bacteriocins; Gram-Positive Bacteria; Humans; Lactococcus; Mannose
PubMed: 35563074
DOI: 10.3390/ijms23094685 -
Journal of Food Protection Dec 1991Wild strains of Listeria monocytogenes , Listeria ivanovii , Listeria seeligeri , Listeria innocua , and Listeria welshimeri were isolated from infected animals and...
Wild strains of Listeria monocytogenes , Listeria ivanovii , Listeria seeligeri , Listeria innocua , and Listeria welshimeri were isolated from infected animals and foodstuffs. Their virulence was tested in Swiss mice after intraperitoneal injection of a fixed number of organisms. The presence of hemolysin was determined using the CAMP test. Bacteria were enumerated in peritoneal lavage fluid, liver, and spleen. Spleen weights were measured, and the presence of L. monocytogenes in the brain was also investigated. L. innocua , L. seeligeri , and L. welshimeri were not found to be pathogenic for mice. L. ivanovii was detected in liver, spleen, and peritoneal lavage fluid but at lower levels than L. monocytogenes (p<0.001). The pathogenic capabilities of four different serovars of L. monocytogenes (4b, 1/2a, 1/2b, 1/2c) were compared. Serovars l/2b and l/2c, which are frequently isolated from foodstuffs, were found to colonize the liver and spleen to a lesser extent than serovar 4b (p<0.01 and <0.001 respectively). The behavior of serovar l/2a, the most commonly isolated from foodstuffs, was strain dependent. Two out of the four strains tested were strongly hemolytic and were as virulent as strains of serovar 4b, while the other two were weakly hemolytic, and avirulent like L. innocua . These results could account for the relatively small number of human Listeria infections due to L. monocytogenes serogroup 1/2, despite the very frequent occurrence of this serovar in foodstuffs.
PubMed: 31071823
DOI: 10.4315/0362-028X-54.12.917