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Selenomonas Ruminantium
''Selenomonas ruminantium'' is a species of ''Selenomonas'' bacteria which are closely associated with ruminants, aiding in digestion of their food. It is predominantly observed in the rumen of these animals, and is strictly anaerobic. Shape and classification The bacterium has a rod shaped structure. Gram classification 16S rRNA gene identification ''Selenomonas ruminantium'' was originally placed with the Gram-positive Firmicutes phylum based on its 16S rRNA gene. It was believed to be correct until the flagellar basal test was performed. Flagellar basal test The observation of flagella under electron microscope revealed the presence of four rings, a typical sign of gram negative species. Observation of the flagellar basal structure confirms that ''S. ruminantium'' has an outer membrane, a characteristic of Gram-negative bacteria . Gram-positive outer membranes or mycomembranes were recently reported for the Gram-positive general ''Corynebacterium'' and ''Mycobacteri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Selenomonas
Members of the genus ''Selenomonas'' (motile crescent-shaped bacteria in general) are referred to trivially as selenomonads. The genus ''Selenomonas'' constitutes a group of motile crescent-shaped bacteria and includes species living in the gastrointestinal tracts of animals, in particular the ruminants. A number of smaller forms discovered with the light microscope are now in culture but many, especially the large selenomonads are not, owing to their fastidious and incompletely known growth requirements. Gram stain The family ''Veillonellaceae'' was transferred from the order ''Eubacteriales'' to the new order ''Selenomonadales'' in the new class '' Negativicutes''. Despite most of the members of the ''Bacillota'' staining positive for the Gram stain and being trivially called "low-GC Gram-positives" (''c.f.'' Bacterial phyla), members of the '' Negativicutes'' stain Gram-negative and possess a double bilayer. This transfer now appears to have been mistaken. On further exam ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ruminants
Ruminants (suborder Ruminantia) are hoofed herbivorous grazing or browsing mammals that are able to acquire nutrients from plant-based food by fermenting it in a specialized stomach prior to digestion, principally through microbial actions. The process, which takes place in the front part of the digestive system and therefore is called foregut fermentation, typically requires the fermented ingesta (known as cud) to be regurgitated and chewed again. The process of rechewing the cud to further break down plant matter and stimulate digestion is called rumination. The word "ruminant" comes from the Latin ''ruminare'', which means "to chew over again". The roughly 200 species of ruminants include both domestic and wild species. Ruminating mammals include cattle, all domesticated and wild bovines, goats, sheep, giraffes, deer, gazelles, and antelopes.Fowler, M.E. (2010).Medicine and Surgery of Camelids, Ames, Iowa: Wiley-Blackwell. Chapter 1 General Biology and Evolution addresses th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anaerobic Organism
An anaerobic organism or anaerobe is any organism that does not require molecular oxygen for growth. It may react negatively or even die if free oxygen is present. In contrast, an aerobic organism (aerobe) is an organism that requires an oxygenated environment. Anaerobes may be unicellular (e.g. protozoans, bacteria) or multicellular. Most fungi are obligate aerobes, requiring oxygen to survive. However, some species, such as the Chytridiomycota that reside in the rumen of cattle, are obligate anaerobes; for these species, anaerobic respiration is used because oxygen will disrupt their metabolism or kill them. Deep waters of the ocean are a common anoxic environment. First observation In his letter of 14 June 1680 to The Royal Society, Antonie van Leeuwenhoek described an experiment he carried out by filling two identical glass tubes about halfway with crushed pepper powder, to which some clean rain water was added. Van Leeuwenhoek sealed one of the glass tubes using a flame and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Firmicutes
The Bacillota (synonym Firmicutes) are a phylum of bacteria, most of which have gram-positive cell wall structure. The renaming of phyla such as Firmicutes in 2021 remains controversial among microbiologists, many of whom continue to use the earlier names of long standing in the literature. The name "Firmicutes" was derived from the Latin words for "tough skin," referring to the thick cell wall typical of bacteria in this phylum. Scientists once classified the Firmicutes to include all gram-positive bacteria, but have recently defined them to be of a core group of related forms called the low- G+C group, in contrast to the Actinomycetota. They have round cells, called cocci (singular coccus), or rod-like forms (bacillus). A few Firmicutes, such as '' Megasphaera'', '' Pectinatus'', ''Selenomonas'' and ''Zymophilus'', have a porous pseudo-outer membrane that causes them to stain gram-negative. Many Bacillota (Firmicutes) produce endospores, which are resistant to desiccation and c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhodobacter Sphaeroides
''Rhodobacter sphaeroides'' is a kind of purple bacterium; a group of bacteria that can obtain energy through photosynthesis. Its best growth conditions are anaerobic phototrophy ( photoheterotrophic and photoautotrophic) and aerobic chemoheterotrophy in the absence of light. ''R. sphaeroides'' is also able to fix nitrogen.De Universiteit van Texas over ''Rhodobacter sphaeroides'' It is remarkably metabolically diverse, as it is able to grow ically via and |
Veillonellaceae
The Veillonellaceae are a family of the Clostridia, formerly known as Acidaminococcaceae. Bacteria in this family are grouped together mainly based on genetic studies, which place them among the Bacillota. Supporting this placement, several species are capable of forming endospores. However, they differ from most other Bacillota in having Gram-negative stains. The cell wall composition is peculiar. Members of this family are all obligate anaerobes, and occur in habitats such as rivers, lakes, and the intestines of vertebrates. They range from spherical forms, such as ''Megasphaera'' and '' Veillonella'', to curved rods, as typified by the Selenomonads. ''Selenomonas'' has a characteristic crescent-shape, with flagella inserted on the concave side, while ''Sporomusa'' is similar but non-motile. Their names refer to this distinctive morphology: ''selene'' means moon, and ''musa'' means banana. The name Selenobacteria also refers to some this group. The description of this ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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