Bacillus anthracisBacillus anthracis is a gram-positive and rod-shaped bacterium that causes anthrax, a deadly disease to livestock and, occasionally, to humans. It is the only permanent (obligate) pathogen within the genus Bacillus. Its infection is a type of zoonosis, as it is transmitted from animals to humans. It was discovered by a German physician Robert Koch in 1876, and became the first bacterium to be experimentally shown as a pathogen.
Gram-negative bacteriaGram-negative bacteria are bacteria that, unlike gram-positive bacteria, do not retain the crystal violet stain used in the Gram staining method of bacterial differentiation. Their defining characteristic is that their cell envelope consists of a thin peptidoglycan cell wall sandwiched between an inner (cytoplasmic) membrane and an outer membrane. These bacteria are found in all environments that support life on Earth.
Bacterial outer membraneThe bacterial outer membrane is found in gram-negative bacteria. Gram-negative bacteria form two lipid bilayers in their cell envelopes - an inner membrane (IM) that encapsulates the cytoplasm, and an outer membrane (OM) that encapsulates the periplasm.
Slime layerA slime layer in bacteria is an easily removable (e.g. by centrifugation), unorganized layer of extracellular material that surrounds bacteria cells. Specifically, this consists mostly of exopolysaccharides, glycoproteins, and glycolipids. Therefore, the slime layer is considered as a subset of glycocalyx. While slime layers and capsules are found most commonly in bacteria, these structures do exist in archaea as well, albeit rarely.
Gram-positive bacteriaGram-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 have a thick layer of peptidoglycan in their cell wall which retains the stain, unlike the thin layer of peptidoglycan in gram-negative bacteria that does not retain the stain.
Haemophilus influenzaeHaemophilus influenzae (formerly called Pfeiffer's bacillus or Bacillus influenzae) is a Gram-negative, non-motile, coccobacillary, facultatively anaerobic, capnophilicpathogenic bacterium of the family Pasteurellaceae.Cell envelopeThe cell envelope comprises the inner cell membrane and the cell wall of a bacterium. In gram-negative bacteria an outer membrane is also included. This envelope is not present in the Mollicutes where the cell wall is absent. Bacterial cell envelopes fall into two major categories: a gram-positive type which stains purple during Gram staining and a gram-negative type which stains pink during Gram staining.
PolysaccharidePolysaccharides (; from Ancient Greek (polús)'many, much' and (sákkhar)'sugar') are "compounds consisting of a large number of monosaccharides linked glycosidically". They are the most abundant carbohydrates in food. Their structures range from linear to highly branched polymers. Examples include storage polysaccharides such as starch, glycogen, and galactogen and structural polysaccharides such as hemicellulose and chitin.
BacteriaDomain of microorganismsSynonyms"Bacteria" (Cohn 1872) Cavalier-Smith 1983"Bacteria" Haeckel 1894"Bacteria" Cavalier-Smith 2002"Bacteriaceae" Cohn 1872a"Bacteriobionta" Möhn 1984"Bacteriophyta" Schussnig 1925"Eubacteria" Woese and Fox 1977"Neobacteria" Möhn 1984"Schizomycetaceae" de Toni and Trevisan 1889"Schizomycetes" Nägeli 1857Bacteria are ubiquitous, mostly free-living organisms often consisting of one biological cell.
GlycocalyxThe glycocalyx (pl.: glycocalyces or glycocalyxes), also known as the pericellular matrix and cell coat, is an external organelle consisting of a layer of glycosylated biomolecules called glycoconjugates, such as glycoproteins and glycolipids. These are embedded in and extend outwards from the cell membranes of virtually all cells.
LipopolysaccharideLipopolysaccharide (LPS), now more commonly known as endotoxin, is a collective term for components of the outermost membrane of the cell envelope of Gram-negative bacteria, such as E. coli and Salmonella with a common structural architecture. Lipopolysaccharides are large molecules consisting of three parts: an outer core polysaccharide termed the O-antigen, an inner core oligosaccharide and lipid A (from which toxicity is largely derived), all covalently linked.
LipoproteinA lipoprotein is a biochemical assembly whose primary function is to transport hydrophobic lipid (also known as fat) molecules in water, as in blood plasma or other extracellular fluids. They consist of a triglyceride and cholesterol center, surrounded by a phospholipid outer shell, with the hydrophilic portions oriented outward toward the surrounding water and lipophilic portions oriented inward toward the lipid center.*As an Amazon Associate I earn from qualifying purchases.