Disease relevance of pIGAL1_03

• I have determined the nucleotide sequence of the ampicillin resistance gene of pBR322, an Escherichia coli plasmid that encodes a penicillin beta-lactamase [1].
• Typing by ERIC2-PCR indicated that the cefoxitin-resistant (FOXr) isolates were distinct. beta-Lactamase studies and hybridization experiments showed that most strains produced beta-lactamases related to the AmpC chromosomal cephalosporinase of Citrobacter freundii [2].
• TEM-1 beta-lactamase is the most prevalent plasmid-mediated beta-lactamase in gram-negative bacteria [3].
• Beta-lactamase expression in Streptomyces cacaoi [4].
• E. coli beta-lactamase (Bla) was used as the reporter protein to determine the functionality of the S-layer signals for heterologous expression and secretion in Lactococcus lactis, Lactobacillus brevis, Lactobacillus plantarum, Lactobacillus gasseri and Lactobacillus casei using a low-copy-number plasmid derived from pGK12 [5].

Psychiatry related information on pIGAL1_03

• This may be because moxalactam acts as a beta lactamase inhibitor for both staphylococcal beta lactamase, as well as the Sabath-Abraham Id type beta lactamase carried by P. aeruginosa (among others) [6].

High impact information on pIGAL1_03

• Cytosolic intermediates of murein biosynthesis and degradation thus act antagonistically to control beta-lactamase expression, thereby operating as a cell-wall sensing device [7].
• Addition of the muropeptide, anhMurNAc-tripeptide, which accumulates in beta-lactamase-overproducing mutants, counteracts the negative effect of UDP-MurNAc-pentapeptide, restoring the innate ability of AmpR to induce ampC expression in vitro [7].
• We have tested mutagenic DNA shuffling for molecular evolution in a beta-lactamase model system [8].
• The X-ray crystal structure of the molecular complex of penicillin G with a deacylation-defective mutant of the RTEM-1 beta-lactamase from Escherichia coli shows how these antibiotics are recognized and destroyed [9].
• Xenopus oocytes can secrete bacterial beta-lactamase [10].

Chemical compound and disease context of pIGAL1_03

• (iii) NB2001 activity against beta-lactamase-producing E. coli is decreased in the presence of the beta-lactamase inhibitor clavulanic acid [11].
• SHV-7, a novel cefotaxime-hydrolyzing beta-lactamase, identified in Escherichia coli isolates from hospitalized nursing home patients [12].
• (ii) Triclosan is detected in NB2001-treated, beta-lactamase-producing Escherichia coli but not in E. coli that does not express beta-lactamase [11].
• In vitro activity of temocillin against extended spectrum beta-lactamase-producing Escherichia coli [13].
• Beta-lactamase TEM1 of E. coli. Crystal structure determination at 2.5 A resolution [14].

Biological context of pIGAL1_03

• A beta-hairpin loop from domain 1 of BLIP is inserted into the active site of the beta-lactamase [15].
• In the first fusion gene blahi, the hinge sequence was directly coupled to the 3' end of the beta-lactamase gene, whereas in the two other constructs, blal1hi and blal2hi, a linker encoding 14 and 10 amino acids, respectively, was inserted between the two subunits [16].
• Unlike conventional beta-lactam antibiotics, where hydrolysis of the beta-lactam ring inactivates the antibiotic, hydrolysis of NB2001 by beta-lactamase releases triclosan [11].
• Nucleotide sequences of CAZ-2, CAZ-6, and CAZ-7 beta-lactamase genes [17].
• Enzyme-catalyzed therapeutic activation (ECTA) is a novel prodrug strategy to overcome drug resistance resulting from enzyme overexpression. beta-Lactamase overexpression is a common mechanism of bacterial resistance to beta-lactam antibiotics [11].

Anatomical context of pIGAL1_03

• Disulphide bridge formation in the periplasm of Escherichia coli: beta-lactamase:: human IgG3 hinge fusions as a model system [16].
• The development of beta-lactamase as a highly versatile genetic reporter for eukaryotic cells [18].
• Since efficient translocation of proteins across biological membranes is thought to be supported by cytoplasmic factors that protect presecretory molecules from being misfolded, these results suggest that both GroES and GroEL proteins possess a chaperone function by which they facilitate export of Bla [19].
• Folding of active beta-lactamase in the yeast cytoplasm before translocation into the endoplasmic reticulum [20].
• Beta-lactamase induction in Enterobacter cloacae, which is linked to peptidoglycan recycling, was investigated by high-performance liquid chromatographic analysis of cell wall fragments in genetically defined cells of Escherichia coli [21].

Associations of pIGAL1_03 with chemical compounds

• The carboxylate of Asp 49 forms hydrogen bonds to four conserved, catalytic residues in the beta-lactamase, thereby mimicking the position of the penicillin G carboxylate observed in the acyl-enzyme complex of TEM-1 with substrate [15].
• These three strains produced two beta-lactamases with pIs of 5.4 (TEM-1) and 7.6. beta-Lactamase assays revealed that the pI 7.6 enzyme hydrolyzed cefotaxime faster (at a relative hydrolysis rate of 30% compared with that of benzylpenicillin) than either ceftazidime or aztreonam (relative hydrolysis rates of 13 and 3.3%, respectively) [12].
• We present here the results for one of the beta-lactamase ECTA compounds, NB2001, which consists of the antibacterial agent triclosan in a prodrug form with a cephalosporin scaffold [11].
• The clinical use of beta-lactam antibiotics combined with beta-lactamase inactivators, such as clavulanate, has resulted in selection of beta-lactamases that are insensitive to inactivation by these molecules [22].
• TEM-7 is a novel broad-spectrum beta-lactamase (Bla), selected in vivo, with a resistance profile similar to that of TEM-1 and TEM-2, but extended to ceftazidime (Caz) and aztreonam [23].

Other interactions of pIGAL1_03

• Standard beta-lactamases K1, P99, TEM-1, SHV-1 and beta-lactamase K-CAZ purified using FPLC through ion-exchange chromatography and filtration chromatography, were identified by determination of isoelectric points, molecular weights and substrate profiles [24].
• Further, a DNA fragment (bla) coding mature beta-lactamase was joined to the region coding the C terminus of the pre-S2 repeat to stabilize the gene product [25].

Analytical, diagnostic and therapeutic context of pIGAL1_03

• Complete nucleotide sequence of a 92-kilobase plasmid harboring the CTX-M-15 extended-spectrum beta-lactamase involved in an outbreak in long-term-care facilities in Toronto, Canada [26].
• Isoelectric focusing did not show any other plasmid-mediated beta-lactamase varieties [27].
• Using liquid chromatography electrospray ionization mass spectrometry, we detected multiple modified proteins when SHV-1 beta-lactamase is inactivated by clavulanate [28].
• Dot blot hybridization and PCR analysis of total bacterial DNA using blaSHV- and blaTEM-specific DNA probes and primers identified the presence of a blaTEM beta-lactamase gene in all of the isolates and a blaSHV gene in the isolates with elevated ceftazidime MICs [29].
• Sequence analysis indicated that bla encodes a polypeptide of 314 amino acid residues [30].

References