Search results
Results from the WOW.Com Content Network
Generally, the basic morphologies are spheres (coccus) and round-ended cylinders or rod shaped (bacillus). But, there are also other morphologies such as helically twisted cylinders (example Spirochetes), cylinders curved in one plane (selenomonads) and unusual morphologies (the square, flat box-shaped cells of the Archaean genus Haloquadratum ...
The crescentin protein is located on the concave face of these cells and appears to be necessary for their shape, as mutants lacking the protein form rod-shaped cells. [2] To influence the shape of the Caulobacter cells, the helices of crescentin filaments associate with the cytoplasmic side of the cell membrane on one lateral side of the cell.
Cell shape is generally characteristic of a given bacterial species, but can vary depending on growth conditions. Some bacteria have complex life cycles involving the production of stalks and appendages (e.g. Caulobacter) and some produce elaborate structures bearing reproductive spores (e.g. Myxococcus, Streptomyces).
The M protein found on some serotypes is also able to prevent opsonization by binding to fibrinogen. [2] However, the M protein is also the weakest point in this pathogen's defense, as antibodies produced by the immune system against M protein target the bacteria for engulfment by phagocytes. M proteins are unique to each strain, and ...
Bacterial morphological plasticity refers to changes in the shape and size that bacterial cells undergo when they encounter stressful environments. Although bacteria have evolved complex molecular strategies to maintain their shape, many are able to alter their shape as a survival strategy in response to protist predators, antibiotics, the immune response, and other threats.
MreB is a protein found in bacteria that has been identified as a homologue of actin, as indicated by similarities in tertiary structure and conservation of active site peptide sequence. The conservation of protein structure suggests the common ancestry of the cytoskeletal elements formed by actin, found in eukaryotes , and MreB, found in ...
Certain bacteria form close spatial associations that are essential for their survival. One such mutualistic association, called interspecies hydrogen transfer, occurs between clusters of anaerobic bacteria that consume organic acids, such as butyric acid or propionic acid, and produce hydrogen, and methanogenic archaea that consume hydrogen. [203]
S. mutans has the following surface protein antigens: glucosyltransferases, protein antigen and glucan-binding proteins. If these surface protein antigens are not present, then the bacteria is a protein antigen-defective mutant with the least susceptibility to phagocytosis therefore causing the least harm to cells. [citation needed]