TEM beta-lactamase [AMR Gene Family]

Accession ARO:3000014
DefinitionTEM-1 is the most commonly-encountered beta-lactamase in gram-negative bacteria. Up to 90% of ampicillin resistance in E. coli is due to the production of TEM-1. Also responsible for the ampicillin and penicillin resistance that is seen in H. influenzae and N. gonorrhoeae in increasing numbers. Although TEM-type beta-lactamases are most often found in E. coli and K. pneumoniae, they are also found in other species of gram-negative bacteria with increasing frequency. The amino acid substitutions responsible for the ESBL phenotype cluster around the active site of the enzyme and change its configuration, allowing access to oxyimino-beta-lactam substrates. Opening the active site to beta-lactam substrates also typically enhances the susceptibility of the enzyme to b-lactamase inhibitors, such as clavulanic acid. Although the inhibitor-resistant beta-lactamases are not ESBLs, they are often discussed with ESBLs because they are also derivatives of the classical TEM- or SHV-type enzymes. These enzymes were at first given the designation IRT for inhibitor-resistant TEM beta-lactamase; however, all have subsequently been renamed with numerical TEM designations. There are at least 19 distinct inhibitor-resistant TEM beta-lactamases. Inhibitor-resistant TEM beta-lactamases have been found mainly in clinical isolates of E. coli, but also some strains of K. pneumoniae, Klebsiella oxytoca, P. mirabilis, and Citrobacter freundii. Although the inhibitor-resistant TEM variants are resistant to inhibition by clavulanic acid and sulbactam, thereby showing clinical resistance to the beta-lactam-lactamase inhibitor combinations of amoxicillin-clavulanate (Co-amoxiclav), ticarcillin-clavulanate, and ampicillin/sulbactam, they normally remain susceptible to inhibition by tazobactam and subsequently the combination of piperacillin/tazobactam, although resistance has been described.
Drug Classmonobactam, cephalosporin, penam, penem
Resistance Mechanismantibiotic inactivation
Classification12 ontology terms | Show
Parent Term(s)5 ontology terms | Show
+ confers_resistance_to_drug_class monobactam [Drug Class]
+ confers_resistance_to_drug_class cephalosporin [Drug Class]
+ confers_resistance_to_drug_class penam [Drug Class]
+ class A beta-lactamase
+ confers_resistance_to_drug_class penem [Drug Class]
Sub-Term(s)
213 ontology terms | Show
+ TEM-1
+ TEM-2
+ TEM-3
+ TEM-4
+ TEM-5
+ TEM-6
+ TEM-7
+ TEM-8
+ TEM-9
+ TEM-10
+ TEM-11
+ TEM-12
+ TEM-13
+ TEM-15
+ TEM-16
+ TEM-17
+ TEM-18
+ TEM-19
+ TEM-20
+ TEM-21
+ TEM-22
+ TEM-24
+ TEM-25
+ TEM-26
+ TEM-27
+ TEM-28
+ TEM-29
+ TEM-30
+ TEM-31
+ TEM-32
+ TEM-33
+ TEM-34
+ TEM-35
+ TEM-36
+ TEM-37
+ TEM-38
+ TEM-39
+ TEM-40
+ TEM-42
+ TEM-43
+ TEM-44
+ TEM-45
+ TEM-46
+ TEM-47
+ TEM-48
+ TEM-49
+ TEM-50
+ TEM-51
+ TEM-52
+ TEM-53
+ TEM-54
+ TEM-55
+ TEM-56
+ TEM-57
+ TEM-58
+ TEM-59
+ TEM-60
+ TEM-61
+ TEM-63
+ TEM-65
+ TEM-66
+ TEM-67
+ TEM-68
+ TEM-70
+ TEM-71
+ TEM-72
+ TEM-73
+ TEM-74
+ TEM-75
+ TEM-76
+ TEM-78
+ TEM-79
+ TEM-80
+ TEM-81
+ TEM-82
+ TEM-83
+ TEM-84
+ TEM-85
+ TEM-86
+ TEM-87
+ TEM-88
+ TEM-89
+ TEM-90
+ TEM-91
+ TEM-92
+ TEM-93
+ TEM-94
+ TEM-95
+ TEM-96
+ TEM-101
+ TEM-102
+ TEM-103
+ TEM-104
+ TEM-105
+ TEM-106
+ TEM-107
+ TEM-108
+ TEM-109
+ TEM-110
+ TEM-111
+ TEM-112
+ TEM-113
+ TEM-114
+ TEM-115
+ TEM-116
+ TEM-117
+ TEM-118
+ TEM-120
+ TEM-121
+ TEM-122
+ TEM-123
+ TEM-124
+ TEM-125
+ TEM-126
+ TEM-127
+ TEM-128
+ TEM-129
+ TEM-130
+ TEM-131
+ TEM-132
+ TEM-133
+ TEM-134
+ TEM-135
+ TEM-136
+ TEM-137
+ TEM-138
+ TEM-139
+ TEM-141
+ TEM-142
+ TEM-143
+ TEM-144
+ TEM-145
+ TEM-146
+ TEM-147
+ TEM-148
+ TEM-149
+ TEM-150
+ TEM-151
+ TEM-152
+ TEM-154
+ TEM-155
+ TEM-156
+ TEM-157
+ TEM-158
+ TEM-159
+ TEM-160
+ TEM-161
+ TEM-162
+ TEM-163
+ TEM-164
+ TEM-165
+ TEM-166
+ TEM-167
+ TEM-168
+ TEM-169
+ TEM-170
+ TEM-171
+ TEM-172
+ TEM-173
+ TEM-174
+ TEM-176
+ TEM-177
+ TEM-178
+ TEM-181
+ TEM-183
+ TEM-186
+ TEM-187
+ TEM-188
+ TEM-189
+ TEM-190
+ TEM-191
+ TEM-192
+ TEM-193
+ TEM-194
+ TEM-195
+ TEM-197
+ TEM-198
+ TEM-199
+ TEM-100
+ TEM-119
+ TEM-140
+ TEM-153
+ TEM-175
+ TEM-179
+ TEM-180
+ TEM-182
+ TEM-185
+ TEM-184
+ TEM-196
+ TEM-200
+ TEM-201
+ TEM-202
+ TEM-203
+ TEM-204
+ TEM-205
+ TEM-206
+ TEM-207
+ TEM-208
+ TEM-209
+ TEM-210
+ TEM-211
+ TEM-212
+ TEM-213
+ TEM-214
+ TEM-215
+ TEM-216
+ TEM-217
+ TEM-218
+ TEM-221
+ TEM-222
+ TEM-219
+ TEM-220
+ TEM-223
Publications

Bradford PA. 2001. Clin Microbiol Rev 14(4): 933-951. Extended-spectrum beta-lactamases in the 21st century: characterization, epidemiology, and detection of this important resistance threat. (PMID 11585791)