|Etymology:||Genus name: named after the German microbiologist Walter Mannheim.|
Species epithet: hemolysing.
|Alternative Species Name(s):||Pasteurella haemolytica, biotype A|
|Type Strain:||J.A. Watt 1266A&B = ATCC 33396 = CCUG 408 and 12392 = NCTC 9380.|
||Medium sized greyish colonies (2-3 mm in diameter). Give a weak hemolysis on horse blood agar, which is easier to observe if the colonies are removed. The hemolysis is easier to observe on bovine blood agar.|
|Micromorphology:||Nonmotile small rod|
|Gram +/Gram -:||G-|
|Other Enzymes:||Tryptophanase -, ornithine decarboxylase -, urease -.|
|Biochemical Tests:||Citrate -, hydrogen sulphide (H2S) -, methyl red -, Voges-Proskauer -.|
|Fermentation of carbohydrates:||
|Virulence Factors:||Adhesines (two membrane proteins OmpA and Lpp1), capsule, endotoxin (toxic for bovine endothelial cells) and leukotoxin (pore-forming cytolysin), which has a potent effect on neutrophiles of ruminants that results in cell death.|
|16S rRNA Seq.:|
||Six 17 have been described within genus Mannheimia. The relationship between members within the closely related genera Actinobacillus, Haemophilus and Pasteurella is very uncertain since none of these genera forms monophyletic clusters.|
|New names of taxa within the classification category phylum|
During October 2021, an article was published by A. Oren och G.M. Garrity, in which new names are proposed for a number of taxa within the classification category phylum. This has resulted in many discussions in social media about whether it was really necessary to make these changes, which have created confusion among microbiologists and other professionals who come into contact with bacteriology.Published 2022-09-28. Read more...