Biomimetic Hydrolysis of Penicillin G Catalyzed by Dinuclear Zinc(II) Complexes: Structure-Activity Correlations in β-Lactamase Model Systems

2005 ◽  
Vol 11 (18) ◽  
pp. 5343-5352 ◽  
Author(s):  
Bernhard Bauer-Siebenlist ◽  
Sebastian Dechert ◽  
Franc Meyer
1980 ◽  
Vol 1 (7) ◽  
pp. 197-201
Author(s):  
Michael J. Kraemer ◽  
Arnold L. Smith

Ampicillin, first introduced in 1961, has probably become the most widely used penicillin in clinical pediatrics. STRUCTURE ACTIVITY RELATIONSHIPS All penicillins contain the 6-amino penicillanic acid moiety (Fig 1). Its structure includes a thiazolidine ring (A), a β-lactam ring (B), the source of antibacterial activity, and an acyl side chain (R), containing a variety of substitutions creating the family of semisynthetic penicillins. The only difference between ampicillin and penicillin G is the presence of an amino group in the acyl side chain (Fig 1). PHARMACOLOGY AND BACTERIOLOGY Ampicillin is a semisynthetic penicillin, active against Streptococus pneumoniae and certain Gram-negative bacteria, including most Haemophilus influenzae, Escherichia coli, and certain Proteus species. Compared to penicillin G, it has increased stability in acid solutions: a property facilitating oral administration and absorption. It penetrates into most body tissues; effective entry into CSF, however, occurs only with inflamed meninges. The serum half-life with normal renal function varies from four hours in newborns1 to 1.3 hours in adults.2 Ampicillin can cause an allergic, or nonallergic skin rash (Fig 2). ALLERGY Allergy (for the purposes of this discussion) is defined as a specific immunologic interaction, between either antigen and antibody, or antigen with a sensitized lymphocyte, resulting in a clinically deleterious effect. Implicit is a prior contact with the antigen.


2010 ◽  
Vol 01 (04) ◽  
pp. 322-329 ◽  
Author(s):  
Neha R. Tiwari ◽  
Ambrish Rathore ◽  
Asmita Prabhune ◽  
Sulabha K. Kulkarni

2019 ◽  
Author(s):  
Philippe Colson ◽  
Lucile Pinault ◽  
Said Azza ◽  
Nicholas Armstrong ◽  
Eric Chabriere ◽  
...  

ABSTRACTEnzymatic proteins with a metallo-beta-lactamase (MBL) fold have been essentially studied in bacteria for their activity on beta-lactam antibiotics. However, the MBL fold is ancient and highly conserved, and these proteins are capable of cleaving a broad range of substrates. It has recently been shown that MBLs are present in a wide array of cellular organisms, including eukaryotes and archaea. We show here that Tupanvirus deep ocean, a giant virus, also encodes a protein with a MBL fold. Phylogeny showed its clustering with transfer ribonucleases (RNases) and the presence of orthologs in other giant viruses, mainly those harboring the largest sets of translation components. In addition, it suggests an ancient origin for these genes and a transfer between giant viruses and Acanthamoeba spp., a host of many giant viruses. Biologically, after its expression in Escherichia coli, the tupanvirus protein was found to hydrolyse nitrocefin, a chromogenic beta-lactam. We also observed an hydrolysis of penicillin G (10 μg/mL) and detected the metabolite of penicillin G hydrolysis, benzylpenilloic acid. This was inhibited by sulbactam, a beta-lactamase inhibitor. In addition, we tested the degradation of single-stranded DNA, double-stranded DNA, and RNAs, and observed a strong activity on RNAs from seven bacteria with G+C varying from 42% to 67%, and from Acanthamoeba castellanii, the tupanvirus host. This was not inhibited by sulbactam or ceftriaxone. RNase activity was estimated to be 0.45±0.15 mU/mg using a fluorescence-based assay. Our results still broaden the range of hosts of MBL fold proteins and demonstrate that such protein can have dual beta-lactamase/nuclease activities. We suggest that they should be annotated according to this finding to avoid further confusion.


2008 ◽  
Vol 136 ◽  
pp. S391
Author(s):  
Mai Ngoc Lan ◽  
Sung Ho Ha ◽  
Yoon-Mo Koo

RSC Advances ◽  
2016 ◽  
Vol 6 (94) ◽  
pp. 91102-91110 ◽  
Author(s):  
Fang Zhao ◽  
Jenny Perez Holmberg ◽  
Zareen Abbas ◽  
Rickard Frost ◽  
Tora Sirkka ◽  
...  

Different levels of model systems are needed for effect studies of engineered nanoparticles and the development of nanoparticle structure–activity relationships in biological systems.


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