The Actinomycetes are a group of Gram-positive mostly anaerobic non-motile bacteria. All species are fungus-like, with filamentous cells producing reproductive spores on aerial branches similar to the spores of certain moulds. The group includes bacteria of the genera Actinomyces, some species of which cause disease in animals and man; and Streptomyces, which are a source of many important antibiotics (including streptomycin). Research Actinomycetes
Escherichia coli (commonly called E. coli) is a species of Gram-negative aerobic bacteria that is found in the intestine and is also widely used in microbiological and genetic research. The motile rod-shaped cells ferment lactose and are usually harmless commensals, although certain strains are pathogenic. Studies of E coli laboratory cultures have revealed much about the genetics of prokaryotes; the species is also frequently used in genetic engineering, particularly as a host for gene cloning and the expression of recombinant foreign genes in culture. Research Escherichia coli
Listeria is a genus of rod-shaped aerobic motile Gram-positive bacteria. Only one species, Listeria monocytogenes, causes disease (listeriosis). It is resistant to physical and chemical treatments and can occur as a contaminant in certain foods, in faeces, etc. Research Listeria
Salmonella is a genus of rod-shaped Gram-negative bacteria that inhabit the intestine and cause disease (salmonellosis) in humans and animals. They are aerobic or facultatively anaerobic, and most are motile.
Salmonellae can exist for long periods outside their host, and may be found, for example, in sewage and surface water. Humans may become infected by consuming contaminated water or food, especially animal products, such as eggs, meat, and milk, or vegetables that have been fertilized with contaminated manure. The bacteria can also be transmitted from human or animalcarriers by unhygienic food preparation. Various species of Salmonella cause gastroenteritis and septicaemia; typhoid fever and paratyphoid fever are caused by Salmonella typhi and Salmonella paratyphi, respectively. Research Salmonella
Staphylococcus is a genus of spherical nonmotile Gram-positive bacteria that occur widely as saprophytes or parasites, the cells occurring in grape-like clusters. Many species inhabit the skin and mucous membranes, and some cause disease in humans and animals. Staphylococcus aureus infection can lead to boils and abscesses in humans; this species also produces toxins that irritate the gastrointestinal tract and result in staphylococcal food poisoning. Research Staphylococcus
Streptococcus is a genus of spherical Gram-positive bacteria occurring widely in nature, typically as chains or pairs of cells. Many are saprophytic and exist as usually harmless commensals inhabiting the skin, mucous membranes, and intestine of humans and animals. Others are parasites, some of which cause diseases, including scarletfever (Streptococcus pyogenes; group A streptococci) , endocarditis (Streptococcus viridans), and pneumonia (Streptococcus pneumoniae). Research Streptococcus
In Norse mythology, Balmung (also known as Gram) was a sword of Siegfried, forged by Wieland the Vulcan. Wieland in a trial of merit, clove Amilias, fellowsmith, through steelhelmet and armour down to the waist; but the cut was so fine that Amilias was not even aware that he was wounded until he attempted to move, where upon he fell into two pieces. Research Balmung
Abbreviations
Research Gram
