?-Lactams and ?-Lactamases
Studies on the inhibition of AmpC and other β-lactamases by cyclic boronates
... lactamase mediated hydrolysis of bicyclic -lactams 15-16, 22 . The binding of the aryl carboxylate is similar in all cases, with differences reflecting the different residues involved in binding this substrate ...
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Surface-bound antibiotic for the detection of beta-lactamases
... explored the robustness of the cephalexin-PEG surface for the detection of β-lactamases in physiological samples, speci fi cally urine. Urine is analyzed routinely for diagnosis and susceptibility testing of ...
7
The development of selective inhibitors of NagZ : increased susceptibility of Gram negative bacteria to β lactams
... The increasing incidence of inducible chromosomal AmpC b- lactamases within the clinic is a growing concern because these enzymes deactivate a broad range of even the most re- cently developed b-lactam ...
10
Identification and preliminary characterization of novel B3 type metallo β lactamases
... mology with B1-type MBLs, hydrolyze exclusively car- bapenems (e.g. meropenem and imipenem) and require only one metal ion for catalysis [5,11]. Representative B2-type MBLs are CphA from Aeromonas hydrophila [12], ImiS ...
6
Extended Spectrum Beta-lactamases: Definition, Classification and Epidemiology
... penicillin have caused changes in ESBLs (Blazquez et al., 2000). As the use of beta- lactams antibiotics was excessive, the ESBLs producer strains were selected. These strains produce different phenotypes and ...
12
Intrinsic Class D β Lactamases of Clostridium difficile
... Combined, our experiments showed that C. difficile strains produce intrinsic broad- spectrum CDD  -lactamases. In the two studied strains, the enzymes are poorly expressed and responsible only partially for the ...
11
A Review of SHV Extended-Spectrum β-Lactamases: Neglected Yet Ubiquitous
... β-lactamases are the primary cause of resistance to β-lactams among members of the family Enterobacteriaceae. SHV enzymes have emerged in Enterobacteriaceae causing infections in health care in the last ...
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Assay platform for clinically relevant metallo-beta-lactamases
... MBLs, which, unlike the SBLs, are not structurally or mechanistically related to the penicillin-binding proteins (PBPs), were fi rst identi fi ed approximately 50 years ago. 9 However, as a result of their apparently ...
10
Synthesis of Some New Spiro β Lactams and Thiazolidinones Compounds Containing Sulfur Incorporating Quinon Compounds
... β-Lactams, being a structural unit found in the most widely used antibiotics [1], have occupied a basic posi- tion in medicinal chemistry for almost a century now. With the microbes basic position in medicinal ...
10
The Mechanisms of Catalysis by Metallo β Lactamases
... Class B β-lactamases or metallo-β-lactamases (MBLs) require zinc-ions to catalyse the hydrolysis of β-lactams and have no sequence or structural homology to the serine β- lactamases. They ...
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Diversity oriented synthesis and activity evaluation of substituted bicyclic lactams as anti malarial against Plasmodium falciparum
... Results: The central scaffold a chiral bicyclic lactam (A) and (A ’ ) which were synthesized from (R)-phenylalaninol, levulinic acid and 3-(2-nitrophenyl) levulinic acid respectively. The DOS library was generated from A ...
11
Occurrence of Extended Spectrum and AmpC Beta Lactamases in Bloodstream Isolates of Klebsiella pneumoniae: Isolates Harbor Plasmid Mediated FOX 5 and ACT 1 AmpC Beta Lactamases
... Unfortunately, few laboratories perform confirmatory tests for AmpC production, and some physicians may assume that carbapenems are the drugs of choice for treating all infections due to Enterobacteriaceae isolates that ...
6
βlasEN: Microdilution Panel for Identifying β Lactamases Present in Isolates of Enterobacteriaceae
... Strains. Tests were performed with 383 isolates of Enterobacteriaceae with well-characterized -lactamases (Table 1) and with 885 clinical isolates from six U.S. Medical Centers. Many of the characterized strains, ...
5
Detection of Extended Spectrum β Lactamases in Klebsiellae with the Oxoid Combination Disk Method
... Extended-spectrum -lactamases (ESBLs) are increasing sources of resistance to oxyimino-aminothiazolyl cephalospo- rins, especially in klebsiellae (1, 9). Most ESBLs are mutant TEM and SHV enzymes, but a few have ...
5
Comparison of Various Phenotypic Methods for the Detection of Metallo-beta-lactamases in Pseudomonas aeruginosa
... immunocompromised individuals, burn patients and Cystic Fibrosis patients. Since that time the organism has become one of the most serious causes of nosocomial bacterial infections notable in the lung, blood and urinary ...
8
Conversions of Cyclic Amines to Nylon Precursor Lactams Using Bulk Gold and Fumed Silica Catalysts
... catalytic conversion of amines to lactams. In the case of piper- idine, valerolactam was produced in >50% yield. In summary, we have developed a heterogeneous catalytic system that is able to perform a tandem ...
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-lactams and Fluoroquinolone Antibiotics in influents and effluents of Wastewater treatment plants, Dar es Salaam, Tanzania
... Variations in levels of antibiotics in WWTPs were considered to be attributed to removal efficiency of individual WWTP and antibiotics prescription patterns in different location[r] ...
6
Preparation of b and g lactams from carbamoyl radicals derived from oxime oxalate amides
... Reactions of the cyclohexenyl (5f ) and cinnamyl (5g) precursors a ff orded the bicyclic β -lactam 12f and the 3-benzyl- substituted β -lactam 12g respectively. In both cases the ring- closed radicals were more stabilised ...
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STUDIES ON THE SYNTHESIS AND IN VITRO ANTIMICROBIAL ACTIVITY EVALUATION OF SOME NOVEL β LACTAMS CONTAINING SULFA DRUGS
... RESULTS AND DISCUSSION: All the β- lactams (c1-c6 and d1-d6) were screened in-vitro for their antibacterial activity against E. coli, P. aeruginosa, B. subtilis and for antifungal activity against A. niger, A. ...
6
Effectiveness of empiric aztreonam compared to other beta-lactams for treatment of <em>Pseudomonas aeruginosa</em> infections
... Agents of choice for empiric therapy are antimicrobials that cover a broad spectrum of bacteria. Empiric therapy for patients at risk of gram-negative infection varies depending on the source of the infection and ...
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