Macrolides organisms

Macrolides containing only neutral sugars were obtained from a platenomycin-producing organism (217,218). Four demycarosyl derivatives of platenomycins were isolated from biosyntheticaHy blocked mutants of S. platensis, two of these possessed a methyl group rather than an aldehyde (219). A pair of novel compounds related to carbomycin were isolated in which one contained an unusual 10,ll-dihydro-12,13-diol moiety, the other a 14-hydroxy-epoxyenone moiety (220). 

The macrolides are effective against a wide variety of pathogenic organisms, particularly infections of die respiratory and genital tract. 

The lincosamides, another group of anti-infectives, are effective against many gram-positive organisms, such as streptococci and staphylococci. However, because of their high potential for toxicity, the lincosamides are usually used only for the treatment of serious infections in which penicillin or erythromycin (a macrolide) is not effective... 

Broad intravenous antibiotic coverage for the encapsulated organisms can include ceftriaxone or cefotaxime. For patients with true cephalosporin allergy, clindamycin may be used. If staphylococcal infection is suspected owing to previous history or the patient appears acutely ill, vancomycin should be initiated. Macrolide antibiotics, such as erythromycin and azithromycin, may be initiated if Mycoplasma pneumonia is suspected. While the patient is receiving broad-spectrum antibiotics, their regular use of penicillin for prophylaxis can be suspended. Fever should be controlled with acetaminophen or ibuprofen. Because of the risk of dehydration during infection with fever, increased fluid may be needed.6,27... 

Ikeda, H., Nonomiya, T., Usami, M. et aL (1999) Organization of the biosynthetic gene cluster for the polyketide anthelmintic macrolide avermectin in Streptomyces avermitilis. Proceedings of the National Academy of Sciences of the United States of America, 96, 9509-9514. 

Acyclic stereocontrol has been a striking concern in modern organic chemistry, and a number of useful methods have been developed for stereoregulated synthesis of conformationally nonrigid complex molecules such as macrolide and polyether antibiotics. Special attention has therefore been paid to the aldol reaction because it constitutes one of the fundamental bond constructions in biosynthesis. 

Andrew Regan was born in Rawtenstall, Lancashire and studied at the University of Cambridge, where he obtained his BA in 1981 (MA 1985), and his PhD in 1984, under the supervision of Professor Jim Staunton. From 1984-1985 he held an SERC-NATO Research Fellowship at Columbia University in the laboratories of Professor Gilbert Stork. He returned to the UK in 1985 to a lectureship in organic chemistry at the University of Kent at Canterbury, and since 1990 has been a lecturer in the Department of Chemistry at the University of Manchester. His research interests include the synthesis of phosphinic-acid hormone mimics, simplified macrolide antibiotics and anti-tumour compounds, stereoselective methodology, and the use of enzymes in synthesis. 

Macrocyclic lattice hosts, 14 111 Macrocyclic mercuracarboranes, 4 216-217 Macrocyclic oligoesters, 25 125 Macrocyclic polymers, 14 252 Macrocyclic polythioethers, 23 707 Macrocylic ligands, 7 576 Macroemulsions, 10 113 16 433-434 Macrofouling organisms, in industrial water treatment, 26 149-150 Macrolide antibiotics, 15 271-320. See also Macrolides... 

Clarithromycin is a macrolide that has a longer half-life than erythromycin so is administered twice daily. Clarithromycin is more active against Grampositive organisms than erythromycin. Clarithromycin may be used in combination with amoxicillin, for example, as part of triple therapy used for the eradication of Helicobacter pylori. 

It is 2-A times less active than erythromycin with respect to a number of streptococci and staphylococci, and to a number of other organisms however, it is more active than other macrolides with respect to certain anaerobic organisms. Like other macrolides, it is active with respect to pathogens of the respiratory tract and pathogens transmitted sexually. It is used for treating bacterial bronchitis, pneumonia, skin, and sexual infections. Synonyms of this drug are zithromax and others. 

Pharmacology Macrolide antibiotics reversibly bind to the P site of the SOS ribosomal subunit of susceptible organisms and inhibit RNA-dependent protein synthesis. They may be bacteriostatic or bactericidal, depending on such factors as drug concentration. 

Rapamycin (sirolimus), a macrolide antibiotic, has been used recently in organ transplantation for its potent immunosuppressive actions by inhibiting both cytokine mediated and growth factor mediated proliferation of smooth muscle cells and lymphocytes [55, 56]. In the RAVEL trial of non-acute single vessel lesions, the Sirolimus-eluting stent was compared to bare metal stent (BMS) in a 1 1 fashion [57]. One-year major adverse cardiovascular events and 6 month neointimal proliferation as assessed by late luminal loss (-0.01 0.33 mm in Sirolimus stent versus 0.80 0.53 mm in BMS) were improved. The Sirolimus-eluting stent thus virtually eliminated in-stent restenosis with no evidence of edge effect, dissection, or in-stent thrombosis. 

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