Disease relevance of TEM-10

• Multiply resistant Klebsiella pneumoniae strains from two Chicago hospitals: identification of the extended-spectrum TEM-12 and TEM-10 ceftazidime-hydrolyzing beta-lactamases in a single isolate [1].
• Ceftazidime-resistant Klebsiella pneumoniae and Escherichia coli isolates producing TEM-10 and TEM-43 beta-lactamases from St. Louis, Missouri [2].
• New variant of TEM-10 beta-lactamase gene produced by a clinical isolate of proteus mirabilis [3].
• Identification of TEM-10 beta-lactamase in a Kluyvera sp. and other Enterobacteriaceae at a Portuguese hospital [4].
• The finding of TEM-10 type and TEM-12 type represents the first detection of a TEM-type ESBL in South America. PER (for Pseudomonas extended resistance)-type beta-lactamases were detected in five of the nine isolates from Turkey and were found with SHV-2-type and SHV-5-type ESBLs in two of the isolates [5].

High impact information on TEM-10

• Both the beta-lactamase inhibitors and the beta-lactamase-resistant antibiotics are themselves beta-lactams, and bacteria have responded to these compounds by expressing variant enzymes resistant to inhibition (e.g. IRT-3) or that inactivate the beta-lactamase-resistant antibiotic (e.g. TEM-10) [6].
• Single point mutations are required to progress from TEM-1 to TEM-12 and from TEM-12 to TEM-10 [1].
• The original TEM-10 plasmid was identical to that found in the E. coli isolate and coded for a gene that corresponded to the TEM-10 beta-lactamase from Tn2 [7].
• Genetically diverse ceftazidime-resistant isolates from a single center: biochemical and genetic characterization of TEM-10 beta-lactamases encoded by different nucleotide sequences [7].
• When the higher inoculum was used, MICs of at least one antimicrobial agent increased at least fourfold in strains producing TEM-3, TEM-10, TEM-28, TEM-43, SHV-5, SHV-18, and K1 [8].

Biological context of TEM-10

• The deduced amino acid sequence indicated the presence of a TEM-10 beta-lactamase [9].

Associations of TEM-10 with other chemical compounds

• Isoelectric focusing results suggested that a predominant enzyme, TEM-10, was responsible for the ceftazidime resistance [10].
• However, the TEM-10 enzyme was inhibited by p-chloromercuribenzoate, in contrast to TEM-2 beta-lactamase [11].
• The in-vitro 50% inhibitory concentrations (IC50s) of latamoxef and imipenem against a set of plasmid-mediated beta-lactamases including TEM-1, TEM-3, TEM-5 and TEM-10 were determined by an enzymatic method using nitrocefin as substrate [12].

Gene context of TEM-10

• Both TEM-10 sequences differed from TEM-1 by substitutions of Ser-162 and Lys-237 [7].
• Ceftazidime-resistant isolates of Escherichia coli and Klebsiella pneumoniae produced a plasmid-mediated beta-lactamase with a pI of 5.6 with biochemical characteristics comparable to those of the TEM-10 beta-lactamase [7].
• When the bacteria were screened for ESBL production and the lower inoculum was used, several strains with ESBLs, including CTX-M-10, TEM-3, TEM-10, TEM-12, TEM-6, SHV-18, and K1, gave false-negative results for one or more antimicrobial agents (MICs below the NCCLS screening concentration for detecting suspected ESBLs) [8].

References