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Listeria Seeligeri
''Listeria seeligeri'' is a Gram-positive, facultatively anaerobic, motile, nonspore-forming, bacillus-shaped species of bacteria. It is not pathogenic. The species was first isolated from plants, soil, and animal feces in Europe, was first proposed in 1983, and is named after Heinz P. R. Seeliger. Seeliger first proposed the species '' L. ivanovii'' and ''L. innocua'', and published extensively on members of the genus ''Listeria''. ''L. seeligeri'' is one of only three species of ''Listeria'' that is hemolytic, along with ''L. ivanovii'' and ''L. monocytogenes ''Listeria monocytogenes'' is the species of pathogenic bacteria that causes the infection listeriosis. It is a Facultative anaerobic organism, facultative anaerobic bacterium, capable of surviving in the presence or absence of oxygen. It can gro ...''.Daniel Weller, Alexis Andrus, Martin Wiedmann and Henk C. den Bakker. Listeria booriae sp. nov. and Listeria newyorkensis sp. nov., from food processing environments in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gram-positive
In bacteriology, gram-positive bacteria are bacteria that give a positive result in the Gram stain test, which is traditionally used to quickly classify bacteria into two broad categories according to their type of cell wall. Gram-positive bacteria take up the crystal violet stain used in the test, and then appear to be purple-coloured when seen through an optical microscope. This is because the thick peptidoglycan layer in the bacterial cell wall retains the stain after it is washed away from the rest of the sample, in the decolorization stage of the test. Conversely, gram-negative bacteria cannot retain the violet stain after the decolorization step; alcohol used in this stage degrades the outer membrane of gram-negative cells, making the cell wall more porous and incapable of retaining the crystal violet stain. Their peptidoglycan layer is much thinner and sandwiched between an inner cell membrane and a bacterial outer membrane, causing them to take up the counterstain ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spore
In biology, a spore is a unit of sexual or asexual reproduction that may be adapted for dispersal and for survival, often for extended periods of time, in unfavourable conditions. Spores form part of the life cycles of many plants, algae, fungi and protozoa. Bacterial spores are not part of a sexual cycle, but are resistant structures used for survival under unfavourable conditions. Myxozoan spores release amoeboid infectious germs ("amoebulae") into their hosts for parasitic infection, but also reproduce within the hosts through the pairing of two nuclei within the plasmodium, which develops from the amoebula. In plants, spores are usually haploid and unicellular and are produced by meiosis in the sporangium of a diploid sporophyte. Under favourable conditions the spore can develop into a new organism using mitotic division, producing a multicellular gametophyte, which eventually goes on to produce gametes. Two gametes fuse to form a zygote which develops into ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Listeria Ivanovii
''Listeria ivanovii'' is a species of bacteria in the genus ''Listeria''. The listeria are rod-shaped bacteria, do not produce spores, and become positively stained when subjected to Gram staining. Of the six bacteria species within the genus, ''L. ivanovii'' is one of the two pathogenic species (the other being ''L. monocytogenes''). In 1955 Bulgaria, the first known isolation of this species was found from sheep. It behaves like ''L. monocytogenes'', but is found almost exclusively in ruminants (mainly sheep). The species is named in honor of Bulgarian microbiologist Ivan Ivanov. This species is facultatively anaerobic, which makes it possible for it to go through fermentation when there is oxygen depletion. Table Morphological, physiological, and biochemical characteristics of ''Listeria ivanovii'' are shown in the Table below. Note: + = Positive, - = Negative L. Ivanovii conony characteristics are observed on nutrient agar plates or slants. Distinction ''Listeria ivanovi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Listeria Innocua
''Listeria innocua'' is a species of Gram-positive, rod-shaped bacteria. It is motile, facultatively anaerobic, and non-spore-forming. ''L. innocua'' was named ''innocua'' (innocuous) because, in contrast to '' Listeria monocytogenes'', it does not readily cause disease in mammals. Another '' Listeria'' species, '' L. seeligeri'', was named after one of the discoverers of ''L. innocua''. Biochemically, ''L. innocua'' is very similar to ''L. monocytogenes'', except that ''L. innocua'' is usually non-hemolytic, arylamidase-positive, and phosphoinositide phospholipase C-negative. Although it is not generally considered a human pathogen, ''L. innocua'' was identified in 2003 as the cause of death of a 62-year-old, otherwise healthy, woman. As with other species in the genus, ''L. innocua'' occurs commonly in the environment (such as soil) and in food. Strains of ''L. innocua'' have been shown to be able to form biofilm A biofilm comprises any syntrophic consortium of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Listeria Monocytogenes
''Listeria monocytogenes'' is the species of pathogenic bacteria that causes the infection listeriosis. It is a facultative anaerobic bacterium, capable of surviving in the presence or absence of oxygen. It can grow and reproduce inside the host's cells and is one of the most virulent foodborne pathogens: 20 to 30% of foodborne listeriosis infections in high-risk individuals may be fatal. Responsible for an estimated 1,600 illnesses and 260 deaths in the United States annually, listeriosis ranks third in total number of deaths among foodborne bacterial pathogens, with fatality rates exceeding even '' Salmonella'' spp. and ''Clostridium botulinum''. In the European Union, listeriosis follows an upward trend that began in 2008, causing 2,161 confirmed cases and 210 reported deaths in 2014, 16% more than in 2013. Listeriosis mortality rates are also higher in the EU than for other foodborne pathogens. ''Listeria monocytogenes'' is a Gram-positive bacterium, in the phylum Bacillot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Listeria
''Listeria'' is a genus of bacteria that acts as an intracellular parasite in mammals. Until 1992, 17 species were known, each containing two subspecies. By 2020, 21 species had been identified. The genus is named in honour of the British pioneer of sterile surgery Joseph Lister. ''Listeria'' species are Gram-positive, rod-shaped, and facultatively anaerobic, and do not produce endospores. The major human pathogen in the genus ''Listeria'' is ''L. monocytogenes''. It is usually the causative agent of the relatively rare bacterial disease listeriosis, an infection caused by eating food contaminated with the bacteria. Listeriosis can cause serious illness in pregnant women, newborns, adults with weakened immune systems and the elderly, and may cause gastroenteritis in others who have been severely infected. Listeriosis is a serious disease for humans; the overt form of the disease has a case-fatality rate of around 20%. The two main clinical manifestations are sepsis an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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