What does chloramphenicol acetyltransferase do?
Chloramphenicol acetyltransferase (or CAT) is a bacterial enzyme (EC 2.3. 1.28) that detoxifies the antibiotic chloramphenicol and is responsible for chloramphenicol resistance in bacteria.
What enzyme is encoded by the chloramphenicol resistance gene?
chloramphenicol acetyltransferase (CAT)
The primary mechanism of resistance to chloramphenicol is due to the presence of chloramphenicol acetyltransferase (CAT), an enzyme which catalyzes the acetylCoA-dependent acetylation of the antibiotic at the C-3 hydroxyl group (58).
Is CAM chloramphenicol?
Chloramphenicol (CAM) [Fig. 1(A)] is a potent broad-spectrum antibacterial agent.
What is the mechanism of action of chloramphenicol?
Chloramphenicol is an antibacterial agent with a broad spectrum of activity against gram-positive bacteria, gram-negative bacteria, and Rickettsia. Its mechanism of action is by inhibition of bacterial protein synthesis by binding with ribosomes.
What is the most common mechanism of resistance to chloramphenicol?
The most common mechanism of resistance to chloramphenicol in bacteria is its enzymatic inactivation by acetylation mainly via acetyltransferases or, in some cases, by chloramphenicol phosphotransferases (1, 56).
What is the CAT gene?
The CAT gene provides instructions for making pieces (subunits) of an enzyme called catalase. Four identical subunits, each attached (bound) to an iron-containing molecule called a heme group, form the functional enzyme.
What are the two antibiotic resistance genes?
The plasmid pBR322 vector carries the genes for tetracycline (tetR) and ampicillin (ampR) resistance. These genes are useful to identify and select the transformants and non-transformants. Was this answer helpful?
Is chloramphenicol an antibiotic?
Chloramphenicol: antibiotic to treat bacterial infections – NHS.
Is CAT a reporter gene?
Chloramphenicol acetyltransferase (CAT) is the classic example among reporter genes. The enzyme catalyzes the transfer of an acetyl remnant of acetyl CoA to chloramphenicol.
What is the structure of chloramphenicol?
C11H12Cl2N2O5Chloramphenicol / Formula
Is chloramphenicol gram-positive or negative?
Chloramphenicol is a broad-spectrum antibiotic whose spectrum includes several gram-positive and gram-negative bacteria, spirochetes, and Rickettsiae.
What bacteria is resistant to chloramphenicol?
Pseudomonas putida KT2440 is a chloramphenicol-resistant bacterium that is able to grow in the presence of this antibiotic at a concentration of up to 25 μg/ml.
What is the pH of catalase?
between pH 7-11
Catalase has an optimum pH of 9 and a working range of between pH 7-11. Most other enzymes function within a working pH range of about pH 5-9 with neutral pH 7 being the optimum.
How are cat patterns determined?
Spots, stripes and blotches: Color patterns of cat fur tracked to a key gene. Researchers discovered some of the genetics behind cat coloring, from Abyssinians and tabbies to leopards and tigers. Color patterns in cats are determined in part by a gene called DKK4.
What are the 3 ways bacteria gain antibiotic resistance?
The three fundamental mechanisms of antimicrobial resistance are (1) enzymatic degradation of antibacterial drugs, (2) alteration of bacterial proteins that are antimicrobial targets, and (3) changes in membrane permeability to antibiotics.
What are antibiotic resistance markers?
Selectable markers are often antibiotic resistance genes (An antibiotic resistance marker is a gene that produces a protein that provides cells expressing this protein with resistance to an antibiotic.).
Is chloramphenicol Gram positive or negative?
Why is lacZ a good reporter gene?
Posted December 10, 2019. The E. coli LacZ gene is often used as a reporter gene since it produces a blue product once it is cleaved by the β-galactosidase enzyme. This ‘reports’ whether or not the gene is expressed by the bacteria when grown in a compatible substrate (such as X-gal).
How is lacZ used as a reporter gene?
coli lacZ gene, when integrated into the mouse genome by transgenic techniques, can be used as a reporter gene under the control of a given promoter/enhancer in a transgene expression cassette. The lacZ gene encodes beta-galactosidase, which catalyzes the cleavage of lactose to form galactose and glucose.
Is chloramphenicol soluble in water?
Chloramphenicol is soluble in ethanol (50mg/ml), butanol, acetone and ethyl acetate, slightly soluble in water (2.5mg/ ml) and insoluble in benzene, petroleum ether and vegetable oil.
What type of bacteria does chloramphenicol work on?
Chloramphenicol is used in human medicine as oral therapy for infections due to vancomycin resistant enterococci (VRE), vancomycin sensitive enterococci, methicillin sensitive Staphylococcus aureus, aerobic gram negative bacteria, and anaerobes such as Bacteroides species.
Why does pH affect catalase?
At extremely high pH levels, the charge of the enzyme will be altered. This changes protein solubility and overall shape. This change in shape of the active site diminishes its ability to bind to the substrate, thus annulling the function of the enzyme (catalase in this case).
Why is pH 7 optimum for catalase?
Catalase pH Levels
If the pH level is lower than 7 or higher than 11, the enzyme becomes denaturated and loses its structure. The liver sustains a neutral pH of about 7, which creates the best environment for catalase and other enzymes.
How is cat coat color determined?
The co-dominant red gene (O/o), found on the X chromosome, determines whether there will be any red variations to fur color or not. This gene encodes phaeomelanin. The dominant allele O codes for orange tones, and the recessive allele o for the non-orange pigmentation (black or brown).
Does a cats pattern change?
If we have a tabby cat, they are subtly changing, every day. Because their fur is striped, the pattern moves over their body and then resets. If we have a cat with spots, or the frosted tips known as “ticking,” they change, too.