Search results
Results from the WOW.Com Content Network
The blue–white screen is a screening technique that allows for the rapid and convenient detection of recombinant bacteria in vector-based molecular cloning experiments. This method of screening is usually performed using a suitable bacterial strain, but other organisms such as yeast may also be used. DNA of transformation is ligated into a ...
The laboratory procedure involves making serial dilutions of the sample (1:10, 1:100, 1:1000, etc.) in sterile water and cultivating these on nutrient agar in a dish that is sealed and incubated. Typical media include plate count agar for a general count or MacConkey agar to count Gram-negative bacteria such as E. coli. Typically one set of ...
Antibiotic resistance tests: Bacteria are streaked on dishes with white disks, each impregnated with a different antibiotic. Clear rings, such as those on the left, show that bacteria have not grown—indicating that these bacteria are not resistant. The bacteria on the right are fully resistant to all but two of the seven antibiotics tested. [33]
This procedure is termed the 'Mantoux technique'. A person who has been exposed to the bacteria would be expected to mount an immune response in the area of skin containing the bacterial proteins. This response is a classic example of 'delayed-type hypersensitivity reaction' ( DTH ), a type IV of hypersensitivities .
The Microtox Model 500 is a laboratory-based photometer that measures acute toxicity.This analyser is a temperature-controlled, self-calibrating biosensor measuring system that uses the bioluminescence of Allivibrio fischeri to determine the toxicity of contaminated water, or elutriates of contaminated soils and sediments.
Diagnostic microbiology is the study of microbial identification. Since the discovery of the germ theory of disease , scientists have been finding ways to harvest specific organisms. Using methods such as differential media or genome sequencing , physicians and scientists can observe novel functions in organisms for more effective and accurate ...
The acidity of the dyes causes them to bind more strongly to the cell walls of the bacteria than to other cells or tissues. This results in the selective staining of only those cells that have a high density of cell wall material, such as acid-fast bacteria. [26] The Ziehl-Neelsen stain is a two step staining process. In the first step, the ...
This is an example of a positive CAMP test indicated by the formation of dark arrowheads where the Strep group B (Streptococcus agalactiae) meets the Staphylococcus aureus (light-yellow/golden middle streak with surrounding dark hemolysis).