1.Profiling of β-lactam selectivity for penicillin-binding proteins in Streptococcus pneumoniae D39.
Kocaoglu O1, Tsui HC2, Winkler ME3, Carlson EE4. Antimicrob Agents Chemother. 2015;59(6):3548-55. doi: 10.1128/AAC.05142-14. Epub 2015 Apr 6.
Selective fluorescent β-lactam chemical probes enable the visualization of the transpeptidase activity of penicillin-binding proteins (PBPs) at different stages of bacterial cell division. To facilitate the development of new fluorescent probes for PBP imaging, we evaluated 20 commercially available β-lactams for selective PBP inhibition in an unencapsulated derivative of the D39 strain of Streptococcus pneumoniae. Live cells were treated with β-lactam antibiotics at different concentrations and subsequently incubated with Bocillin FL (Boc-FL; fluorescent penicillin) to saturate uninhibited PBPs. Fluorophore-labeled PBPs were visualized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and fluorescence scanning. Among 20 compounds tested, carbapenems (doripenem and meropenem) were coselective for PBP1a, PBP2x, and PBP3, while six of the nine penicillin compounds were coselective for PBP2x and PBP3. In contrast, the seven cephalosporin compounds tested display variability in their PBP-binding profiles.
2.p-aminohippuric acid transport at renal apical membrane mediated by human inorganic phosphate transporter NPT1.
Uchino H1, Tamai I, Yamashita K, Minemoto Y, Sai Y, Yabuuchi H, Miyamoto Ki, Takeda E, Tsuji A. Biochem Biophys Res Commun. 2000 Apr 2;270(1):254-9.
Organic anions are secreted into urine via organic anion transporters across the renal basolateral and apical membranes. However, no apical membrane transporter for organic anions such as p-aminohippuric acid (PAH) has yet been identified. In the present study, we showed that human NPT1, which is present in renal apical membrane, mediates the transport of PAH. The K(m) value for PAH uptake was 2.66 mM and the uptake was chloride ion sensitive. These results are compatible with those reported for the classical organic anion transport system at the renal apical membrane. PAH transport was inhibited by various anionic compounds. Human NPT1 also accepted uric acid, benzylpenicillin, faropenem, and estradiol-17beta-glucuronide as substrates. Considering its chloride ion sensitivity, Npt1 is expected to function for secretion of PAH from renal proximal tubular cells. This is the first molecular demonstration of an organic anion transport function for PAH at the renal apical membrane.
3.Gateways to clinical trials.
Tomillero A, Moral MA. Methods Find Exp Clin Pharmacol. 2008 Oct;30(8):643-72.
Gateways to clinical trials is a guide to the most recent trials in current literature and congresses. The data in the following tables has been retrieved from the Clinical Trials Knowledge Area of Prous Science Integrity(R), the drug discovery and development portal, http://integrity.prous.com. This issue focuses on the following selection of drugs: (+)-Dapoxetine hydrochloride, (S)-Tenatoprazole sodium salt monohydrate 19-28z, Acotiamide hydrochloride hydrate, ADV-TK, AE-37, Aflibercept, Albinterferon alfa-2b, Aliskiren fumarate, Asenapine maleate, Axitinib; Bavituximab, Becatecarin, beta-1,3/1,6-Glucan, Bevacizumab, Bremelanotide; Calcipotriol/betamethasone dipropionate, Casopitant mesylate, Catumaxomab, CDX-110, Cediranib, CMD-193, Cositecan; Darinaparsin, Denosumab, DP-b99, Duloxetine hydrochloride; E75, Ecogramostim, Elacytarabine, EMD-273063, EndoTAG-1, Enzastaurin hydrochloride, Eplerenone, Eribulin mesilate, Esomeprazole magnesium, Etravirine, Everolimus, Ezetimibe; Faropenem daloxate, Febuxostat, Fenretinide; Ghrelin (human); I-131 ch-TNT-1/B, I-131-3F8, Iclaprim, Iguratimod, Iloperidone, Imatinib mesylate, Inalimarev/Falimarev, Indacaterol, Ipilimumab, Iratumumab, Ispinesib mesylate, Ixabepilone; Lapatinib ditosylate, Laquinimod sodium, Larotaxel dehydrate, Linezolid, LOR-2040; Mapatumumab, MKC-1, Motesanib diphosphate, Mycophenolic acid sodium salt; NK-012; Olanzapine pamoate, Oncolytic HSV, Ortataxel; Paclitaxel nanoparticles, Paclitaxel poliglumex, Paliperidone palmitate, Panitumumab, Patupilone, PCV-9, Pegfilgrastim, Peginterferon alfa-2a, Peginterferon alfa-2b, Pertuzumab, Picoplatin, Pimavanserin tartrate, Pimecrolimus, Plerixafor hydrochloride, PM-02734, Poly I:CLC, PR1, Prasugrel, Pregabalin, Progesterone caproate, Prucalopride, Pumosetrag hydrochloride; RAV-12, RB-006, RB-007, Recombinant human erythropoietin alfa, Rimonabant, Romidepsin; SAR-109659, Satraplatin, Sodium butyrate; Tadalafil, Talampanel, Tanespimycin, Tarenflurbil, Tariquidar, Taurine, Tecovirimat, Telatinib, Telavancin hydrochloride, Telcagepant, Terameprocol, Tesofensine, Tetrodotoxin, Tezampanel, Tipifarnib, TPI-287, Tremelimumab; Valspodar, Vatalanib succinate, VCL-CB01, vCP1452, Vorinostat; XL-228; Ziprasidone hydrochloride.
4.Synthesis, characterization and antibacterial activities of some new ferrocene-containing penems.
Long B1, He C, Yang Y, Xiang J. Eur J Med Chem. 2010 Mar;45(3):1181-8. doi: 10.1016/j.ejmech.2009.12.045. Epub 2009 Dec 28.
The synthesis and structure-activity relationships of a series of new penems bearing ferrocenyl group attached to the C-2 position of the penem nucleus were described. The beta-lactanic derivatives obtained had been characterized as sodium salts, through (1)H NMR and IR, as well as through element analysis. Their in vitro antibacterial activities against both Gram-positive including meticillin-resistant Staphylococcus aureus (MRSA) and Gram-negative bacteria were tested. Most of the penems exhibited superior or equivalent efficacy of antibacterial activity as well as high stability to renal dehydropeptidase-I (DHP-I) compared with faropenem. In particular, the compound 14h having a heterocyclic group showed the most potent antibacterial activity.