Extended spectrum beta-lactamase (ESBL) that inactivates beta-lactam antibiotics by hydrolyzing the amide group of the beta-lactam ring. Displays high levels of penicillinase and cephalosporinase activity as well as measurable activity with carbapenems, including imipenem and meropenem. Plays a primary role in the intrinsic resistance of M.tuberculosis to beta-lactam antibiotics. a beta-lactam + H2O = a substituted beta-amino acid Is inhibited by sulbactam, tazobactam, and clavulanate. Sulbactam inhibits the enzyme competitively and reversibly with respect to nitrocefin. Tazobactam inhibits the enzyme in a time-dependent manner, but the activity of the enzyme reappears due to the slow hydrolysis of the covalently acylated enzyme. In contrast, clavulanate reacts with the enzyme quickly to form hydrolytically stable, inactive forms of the enzyme, via irreversible acylation of the catalytic serine residue. Clavulanate has potential to be used in combination with approved beta-lactam antibiotics to treat multi-drug resistant (MDR) and extremely drug resistant (XDR) strains of M.tuberculosis. Is also irreversibly inhibited by NXL104, which forms an extremely stable carbamoyl adduct with the enzyme but shows an inhibition efficiency more than 100-fold lower than that of clavulanate. Is inhibited by carbapenems, that are very poor substrates for the enzyme. kcat is 600 min(-1) with ampicillin as substrate. kcat is 340 min(-1) with amoxicillin as substrate. kcat is 560 min(-1) with penicillin G as substrate. kcat is 2100 min(-1) with penicillin V as substrate. kcat is 690 min(-1) with piperacillin as substrate. kcat is 1070 min(-1) with cephalosporin C as substrate. kcat is 490 min(-1) with cephalotin as substrate. kcat is 490 min(-1) with cefuroxime as substrate. kcat is 3500 min(-1) with cefamandole as substrate. kcat is 48 min(-1) with cefoxitin as substrate. kcat is 2.0 min(-1) with ceftazidime as substrate. kcat is 49 min(-1) with ceftriaxone as substrate. kcat is 380 min(-1) with cefotaxime as substrate. kcat is 6680 min(-1) with nitrocefin as substrate. kcat is 1770 min(-1) with CENTA as substrate. kcat is 10 min(-1) with imipenem as substrate. kcat is 0.08 min(-1) with meropenem as substrate. Assays above performed at pH 6.4. kcat is 18.5 sec(-1) with ampicillin as substrate. kcat is 12.1 sec(-1) with cephalotin as substrate. kcat is 1.1 sec(-1) with cefoxitin as substrate. kcat is 0.2 sec(-1) with ceftazidime as substrate. kcat is 0.9 sec(-1) with meropenem as substrate. Assays above performed at pH 7.5. kcat is 0.08 min(-1) with meropenem as substrate at pH 6.5. kcat is 0.016 min(-1) with doripenem as substrate. kcat is 0.017 min(-1) with ertapenem as substrate. kcat is 0.65 min(-1) with faropenem as substrate. Assays above performed at pH 6.5. Monomer. Constitutively expressed. Exported by the Tat system. The position of the signal peptide cleavage has not been experimentally proven. Cells lacking this gene become significantly more susceptible (16- to 32-fold) to penicillins as well as third-generation cephalosporins and carbapenems. They have no detectable beta-lactamase activity. Can be used as a biomarker, which together with BlaC-specific fluorogenic substrates, allows a rapid and accurate detection of very low numbers of M.tuberculosis for the clinical diagnosis of tuberculosis in sputum and other specimens. Belongs to the class-A beta-lactamase family.