Search results
Results from the WOW.Com Content Network
It is ideally spatially unstructured and temporally unstructured, in a steady state defined by the rates of nutrient supply and bacterial growth. In comparison to batch culture, bacteria are maintained in exponential growth phase, and the growth rate of the bacteria is known. Related devices include turbidostats and auxostats.
The primary site of infection is the intestinal epithelium, where the bacteria invade nonphagocytic cells via the "zipper" mechanism. Uptake is stimulated by the binding of listerial internalins (Inl) to E-cadherin, a host cell adhesion factor, or Met , hepatocyte growth factor.
Bacteria grow to a fixed size and then reproduce through binary fission, a form of asexual reproduction. [114] Under optimal conditions, bacteria can grow and divide extremely rapidly, and some bacterial populations can double as quickly as every 17 minutes. [115] In cell division, two identical clone daughter cells are produced. Some bacteria ...
Some types of bacteria can only grow in the presence of certain additives. This can also be used when creating engineered strains of bacteria that contain an antibiotic-resistance gene. When the selected antibiotic is added to the agar, only bacterial cells containing the gene insert conferring resistance will be able to grow.
Drug resistant bacteria multiply as well, but upon drug treatment, the bacteria continue to spread. [ 13 ] The WHO defines antimicrobial resistance as a microorganism's resistance to an antimicrobial drug that was once able to treat an infection by that microorganism. [ 3 ]
In microbiology, a colony-forming unit (CFU, cfu or Cfu) is a unit which estimates the number of microbial cells (bacteria, fungi, viruses etc.) in a sample that are viable, able to multiply via binary fission under the controlled conditions. Counting with colony-forming units requires culturing the microbes and counts only viable cells, in ...
A prokaryote is defined as having no cell nucleus or other membrane bound-organelle. Archaea share this defining feature with the bacteria with which they were once grouped. In 1990 the microbiologist Woese proposed the three-domain system that divided living things into bacteria, archaea and eukaryotes, [42] and thereby split the prokaryote ...
The bacteria are not able to reproduce at pH levels lower than 5.0. In addition, Bordetella pertussis favors a temperature range of 35 °C to 37 °C. [ 12 ] It is a strict aerobe as mentioned previously and its nutritional requirements are meticulous in its requirement for nicotinamide supplement.