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Carbapenemase
Beta-lactamases (β-lactamases) are enzymes () produced by bacteria that provide multi-resistance to beta-lactam antibiotics such as penicillins, cephalosporins, cephamycins, monobactams and carbapenems (ertapenem), although carbapenems are relatively resistant to beta-lactamase. Beta-lactamase provides antibiotic resistance by breaking the antibiotics' structure. These antibiotics all have a common element in their molecular structure: a four-atom ring known as a beta-lactam (β-lactam) ring. Through hydrolysis, the enzyme lactamase breaks the β-lactam ring open, deactivating the molecule's antibacterial properties. Beta-lactamases produced by gram-negative bacteria are usually secreted, especially when antibiotics are present in the environment. Structure The structure of a ''Streptomyces'' serine β-lactamase (SBLs) is given by . The alpha-beta fold () resembles that of a DD-Transpeptidase, DD-transpeptidase, from which the enzyme is thought to have evolved. β-l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ESBL Stokes
Beta-lactamases (β-lactamases) are enzymes () produced by bacteria that provide Multiple drug resistance, multi-resistance to beta-lactam antibiotics such as penicillins, cephalosporins, cephamycins, monobactams and carbapenems (ertapenem), although carbapenems are relatively resistant to beta-lactamase. Beta-lactamase provides antibiotic resistance by breaking the antibiotics' structure. These antibiotics all have a common element in their molecular structure: a four-atom ring known as a beta-lactam (β-lactam) ring. Through hydrolysis, the enzyme lactamase breaks the β-lactam ring open, deactivating the molecule's antibacterial properties. Beta-lactamases produced by gram-negative bacteria are usually secreted, especially when antibiotics are present in the environment. Structure The structure of a ''Streptomyces'' serine β-lactamase (SBLs) is given by . The alpha-beta fold () resembles that of a DD-Transpeptidase, DD-transpeptidase, from which the enzyme is thoug ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
New Delhi Metallo-beta-lactamase 1
NDM-1 is an enzyme that makes bacteria Antibiotic resistance, resistant to a broad range of beta-lactam antibiotics. These include the antibiotics of the carbapenem family, which are a mainstay for the treatment of antibiotic-resistant bacterial infections. The gene for NDM-1 is one member of a large gene family that encodes beta-lactamase enzymes called Beta-lactamase#Carbapenemases, carbapenemases. Bacteria that produce carbapenemases are often referred to in the news media as "Antibiotic resistance, superbugs" because infections caused by them are difficult to treat. Such bacteria are usually sensitive only to polymyxins and tigecycline. NDM-1 was first detected in 2008 in a culture plate of ''Klebsiella pneumoniae'' isolated from a Sweden, Swedish patient of Indian origin. It was later detected in bacteria in India, Pakistan, the United Kingdom, the United States, Canada, Japan, Egypt, and Iraq. The most common bacteria that make this enzyme are Gram-negative bacteria, gram-n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbapenem
Carbapenems are a class of very effective antibiotic agents most commonly used for treatment of severe bacterial infections. This class of antibiotics is usually reserved for known or suspected multidrug-resistant (MDR) bacterial infections. Similar to penicillins and cephalosporins The cephalosporins (sg. ) are a class of β-lactam antibiotics originally derived from the fungus ''Acremonium'', which was previously known as ''Cephalosporium''. Together with cephamycins, they constitute a subgroup of β-lactam antibiotic ..., carbapenems are members of the beta-lactam antibiotics drug class, which kill bacteria by binding to penicillin-binding proteins, thus inhibiting bacterial cell wall synthesis. However, these agents individually exhibit a broader spectrum of activity compared to most cephalosporins and penicillins. Furthermore, carbapenems are typically unaffected by emerging antibiotic resistance, even to other beta-lactams. Carbapenem antibiotics were originall ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antibiotic Resistance
Antimicrobial resistance (AMR or AR) occurs when microbes evolve mechanisms that protect them from antimicrobials, which are drugs used to treat infections. This resistance affects all classes of microbes, including bacteria (antibiotic resistance), viruses (antiviral resistance), parasites (antiparasitic resistance), and fungi (antifungal resistance). Together, these adaptations fall under the AMR umbrella, posing significant challenges to healthcare worldwide. Misuse and improper management of antimicrobials are primary drivers of this resistance, though it can also occur naturally through genetic mutations and the spread of resistant genes. Antibiotic resistance, a significant AMR subset, enables bacteria to survive antibiotic treatment, complicating infection management and treatment options. Resistance arises through spontaneous mutation, horizontal gene transfer, and increased selective pressure from antibiotic overuse, both in medicine and agriculture, which accelerat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Multiple Drug Resistance
Multiple drug resistance (MDR), multidrug resistance or multiresistance is antimicrobial resistance shown by a species of microorganism to at least one antimicrobial drug in three or more antimicrobial categories. Antimicrobial categories are classifications of antimicrobial agents based on their mode of action and specific to target organisms. The MDR types most threatening to public health are MDR bacteria that resist multiple antibiotics; other types include MDR viruses, parasites (resistant to multiple antifungal, antiviral, and antiparasitic drugs of a wide chemical variety). Recognizing different degrees of MDR in bacteria, the terms ''extensively drug-resistant'' (''XDR'') and ''pandrug-resistant'' (''PDR'') have been introduced. ''Extensively drug-resistant (XDR)'' is the non-susceptibility of one bacteria species to all antimicrobial agents except in two or less antimicrobial categories. Within XDR, ''pandrug-resistant (PDR)'' is the non-susceptibility of bacteria to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ertapenem
Ertapenem, sold under the brand name Invanz, is a carbapenem antibiotic medication used for the treatment of infections of the abdomen, the lungs, the upper part of the female reproductive system, and the diabetic foot. The most common side effects include diarrhoea, nausea, headache, and problems around the area where the medicine is infused. It can significantly reduce the concentrations of valproic acid, an anti-seizure medication, in the blood to the point where it loses its effectiveness. Ertapenem was approved for medical use in the United States in November 2001, and in the European Union in April 2002. It is marketed by Merck. Medical uses Ertapenem is indicated for the treatment of intra-abdominal infections, community-acquired pneumonia, pelvic infections, and diabetic foot infections, with bacteria that are susceptible to this drug, or expected to be so. It can also be used to prevent infections after colorectal surgery. In the United States it is also indicate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RNase Z
TRNase Z (, ''3 tRNase'', ''tRNA 3 endonuclease'', ''RNase Z'', ''3' tRNase'') is an enzyme that, among other things, catalyses the reactions involved in the maturation of tRNAs. Here, it endonucleolytically cleaves the RNA and removes extra 3' nucleotides from the tRNA precursor, generating the 3' termini of tRNAs. A 3'-hydroxy group In chemistry, a hydroxy or hydroxyl group is a functional group with the chemical formula and composed of one oxygen atom covalently bonded to one hydrogen atom. In organic chemistry, alcohols and carboxylic acids contain one or more hydroxy ... is left at the tRNA terminus and a 5'- phosphoryl group is left at the trailer molecule. Similarly, it processes tRNA-like molecules such as mascRNA. References External links * {{Portal bar, Biology, border=no EC 3.1.26 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methicillin
Methicillin ( USAN), also known as meticillin ( INN), is a narrow-spectrum β-lactam antibiotic of the penicillin class. Methicillin was discovered in 1960. Medical uses Compared to other penicillins that face antimicrobial resistance due to β-lactamase, it is less active, can be administered only parenterally, and has a higher frequency of interstitial nephritis, an otherwise-rare adverse effect of penicillins. However, selection of methicillin depended on the outcome of susceptibility testing of the sampled infection, and since it is no longer produced, it is also not routinely tested for any more. It also served a purpose in the laboratory to determine the antibiotic sensitivity of ''Staphylococcus aureus'' to other penicillins facing β-lactam resistance; this role has now been passed on to other penicillins, namely '' cloxacillin'', as well as genetic testing for the presence of '' mecA'' gene by '' PCR''. Spectrum of activity At one time, methicillin was u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Streptomyces Albus
''Streptomyces albus'' is a bacteria Bacteria (; : bacterium) are ubiquitous, mostly free-living organisms often consisting of one Cell (biology), biological cell. They constitute a large domain (biology), domain of Prokaryote, prokaryotic microorganisms. Typically a few micr ...l species from which the pseudodisaccharide aminoglycoside salbostatin was isolated. ''S. albus'' is known to produce white aerial mycelium. References Further reading * External linksType strain of ''Streptomyces albus'' at Bac''Dive'' - the Bacterial Diversity Metadatabase albus {{Streptomyces-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enterobacter Cloacae
''Enterobacter cloacae'' is a clinically significant Gram-negative, facultatively-anaerobic, rod-shaped bacterium. Microbiology In microbiology laboratories, ''E. cloacae'' is frequently grown at 30 °C on nutrient agar or at 35 °C in tryptic soy broth. It is a rod-shaped, Gram-negative Gram-negative bacteria are bacteria that, unlike gram-positive bacteria, do not retain the crystal violet stain used in the Gram staining method of bacterial differentiation. Their defining characteristic is that their cell envelope consists ... bacterium, is facultatively anaerobic, and bears peritrichous flagella. It is oxidase-negative and catalase-positive. Industrial use ''Enterobacter cloacae'' has been used in a bioreactor-based method for the biodegradation of explosives and in the biological control of plant diseases. ''Enterobacter cloacae'' strain MBB8 isolated from the Gulf of Mannar, India was reported to degrade poly vinyl alcohol (PVA). This was the f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DD-Transpeptidase
DD-Transpeptidase (, ''DD-peptidase'', ''DD-transpeptidase'', ''DD-carboxypeptidase'', ''D-alanyl-D-alanine carboxypeptidase'', ''D-alanyl-D-alanine-cleaving-peptidase'', ''D-alanine carboxypeptidase'', ''D-alanyl carboxypeptidase'', and ''serine-type D-Ala-D-Ala carboxypeptidase''.) is a bacterial enzyme that catalyzes the transfer of the R-L-αα-D-alanyl moiety of R-L-αα-D-alanyl-D-alanine carbonyl donors to the γ-OH of their active-site serine and from this to a final acceptor. It is involved in bacterial cell wall biosynthesis, namely, the transpeptidation that crosslinks the peptide side chains of peptidoglycan strands. The antibiotic penicillin irreversibly binds to and inhibits the activity of the transpeptidase enzyme by forming a highly stable penicilloyl-enzyme intermediate. Because of the interaction between penicillin and transpeptidase, this enzyme is also known as penicillin-binding protein (PBP). Mechanism DD-Transpeptidase is mechanistically similar to the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
