by Dr.Sawsan Sajid & Dr. Ibtesam G.Auda

Slides:



Advertisements
Similar presentations
Dr.T.V.Rao MD CLINDAMYCIN USES AND CONCERNS DR.T.V.RAO MD 1.
Advertisements

PHL 424 Antimicrobials 9 th Lecture By Abdelkader Ashour, Ph.D. Phone:
PHL 424 Antimicrobials 6 th Lecture By Abdelkader Ashour, Ph.D. Phone:
Antibiotics Biotechnology II. Univ S. Carolina Antibiotics Disrupt Cell Wall Synthesis, Protein Synthesis, Nucleic Acid Synthesis and Metabolism.
Drugs acting on bacterial protein biosynthesis
Clindamycin induction test in treating patients infected with methicilin resistant Staphylococcus aureus Presented by Iyad Kaddora.
Protein synthesis inhibitors: M.Sc. In Pharm (Pharmacology)
Non-pharmacologic Elevate the affected area to facilitate gravity drainage of edema and inflammatory substances – Patients with edema may benefit from.
Antibacterial Inhibitors of Cell Wall Synthesis –Very high therapeutic index Low toxicity with high effectiveness β- lactam Drugs –Inhibit peptidoglycan.
Antimicrobial compounds Antiseptics and disinfectants Antibiotics.
1 Inhibitors of Protein Synthesis Bacterial cells are 50% protein by dry weight –Inhibition of protein synthesis leads to cessation of growth or cell death.
Chemical Control Methods
AMINOGLYCOSIDES The different members of this group share many properties in common. The different members of this group share many properties in common.
Medications for the Treatment of Infections. Antibiotic vs. Antibacterial Used interchangeably Origin of antibiotic includes any antimicrobial agent Antibacterial.
Copyright © 2008 Lippincott Williams & Wilkins. Introductory Clinical Pharmacology Chapter 9 Tetracyclines, Macrolides, and Lincosamides.
By: Azreena (D11A005) & Nur Nabila (D11A027)
PHL 424 Antimicrobials 5 th Lecture By Abdelkader Ashour, Ph.D. Phone:
Inhibiting Microbial Growth in vivo CLS 212: Medical Microbiology.
Pharmacology Unit 2: Applied Surgical Pharmacology Elsevier items and derived items © 2006 by Saunders, an imprint of Elsevier Inc.
CLINICAL PHARMACOLOGY OF ANTIBACTERIAL AGENTS. Actions of antibacterial drugs on bacterial cells.
Antimicrobial Drugs.
Chapter 15: Antimicrobial Drugs ChemotherapyThe use of drugs to treat a disease Antimicrobial drugsInterfere with the growth of microbes within a host.
Antimicrobial drugs. Antimicrobial drugs are effective in the treatment of infections because of their selective toxicity (that is, they have the ability.
1 Drugs that Inhibit Cell wall synthesis Beta-lactams –Penicillin family –Cephalosporin family –Carbapenems and Monobactams –Β-lactamase inhibitors Vancomycin.
Inhibiting Microbial Growth in vivo CLS 212: Medical Microbiology.
Treatment Of Respiratory Tract infections. Prof. Azza ELMedany Department of Pharmacology Ext
 Antimicrobial agents share certain common properties.  We can learn much about how these agents work and why they sometimes do not work by considering.
Lecture: 6 MACROLIDES. Among the many antibiotics isolated from the actinomycetes is the group of chemically related compounds called the macrolides.
Antibiotics (anti-microbials)
PRINCIPLES OF ANTIBIOTIC THERAPY
Bacteriostatic Inhibitors of Protein Synthesis: Tetracyclines, Macrolides, and Others.
MISCELLANEOUS DRUGS.
Antibiotics By Alaina Darby.
Protein Synthesis Inhibitors
Drugs and Microbes.
Antibiotic Resistance
15th International Symposium on Staphylococci and Staphylococcal Infections 26th-30th August 2012 Lyon, France Prevalence and mechanism of resistance.
Miscellaneous Antibiotics
Antimicrobial Susceptibility Testing (AST)
Antibacterial Drugs General Terminology Mindy Valenti
Aminoglycosides.
Interior Health Pharmacy Resident Kootenay Lake Hospital
Diseases caused by Staph. aureus
Lecture 1 Antimicrobial drugs.
Chapter 20-Antimicrobial Agents
By :Lecturer Nabeel Ahmed Al anbagi
Drugs used in Meningitis Prof. Azza ELMedany
Inhibitors of Protein Synthesis
Presentation on Antibiotics & its Resistance
CHEMOTHERAPY ANTIBIOTICS Chemical substances produced by microorganisms and have the capacity to inhibit or destroy other organisms . CHEMOTHERAPEUTIC.
Cephalosporin and Other Cell Wall Synthesis Inhibitors
Surgical Infection Society Resident Corner
Antiprotozoal Drugs Protozoal infections are common among people in underdeveloped tropical and subtropical countries, where sanitary conditions, hygienic.
Cephalosporin and Cell Wall Synthesis Inhibitors
Drugs that Inhibit Cell wall synthesis
Other Protein Synthesis Inhibitor
Antimicrobial Medications
Chemotherapeutic agent
Antibiotic Resistance
Drug Resistance Bacteria are considered resistant to an antibiotic if the maximal level of that antibiotic that can be tolerated by the host does not halt.
Broad-spectrum antibiotics
Cephalosporin and Cell Wall Synthesis Inhibitors
Antibacterial Agents: Protein Synthesis Inhibitor Antibiotics
Drugs used in Meningitis Prof. M. Alhumayyd Prof. Hanan hagar
Other Protein Synthesis Inhibitor
Other β-lactam A. Carbapenems:
Current Threats to Public Health
2- Tetracyclines Classification
Cell Wall Synthesis Inhibitors (Penicillins)
ANTIBIOTICS They are divided into four categories based on their bacteriostatic or bactericidal effect(mode of action) on various structures and macromolecules.
Presentation transcript:

by Dr.Sawsan Sajid & Dr. Ibtesam G.Auda 8th lecture in antibiotics : biotechnology Other protein synthesis inhibitors Lincosamides and Streptogramins by Dr.Sawsan Sajid & Dr. Ibtesam G.Auda

Lincosamides is a class of antibacterials originates from a natural product, and was first characterized in the 1960s. lincomycin is the first lincosamide to be discovered , isolated from Streptomyces lincolnensis in a soil sample from Lincoln, Nebraska (hence the bacterial name). The semi synthetic derivatives are clindamycin and pirlimycin. now it is used to treat a broad spectrum of infections. It is mostly active against gram-positive organisms, but also finds use against selected gram-negative anaerobes and protozoa. Mode of action :These antibiotics function by blocking microbial protein synthesis via binding to the 23S rRNA of the 50S subunit and mimicking the intermediate formed in the initial phase of the elongation cycle

Structure of licncomycines

Spectrum of activity : Usage of lincomycin has been largely superseded by clindamycin which exhibits improved antibacterial activity. Clindamycin also exhibits some activity against parasitic protozoa and has been used for toxoplasmosis and malaria. Lincosamides are normally used to treat Staphylococcus and Streptococcus and have proved useful in treating Bacteroides fragilis and some other anaerobes. They are used in the treatment of toxic shock syndrome and thought to directly block the M protein production that leads to the severe inflammatory response. مهم Lincosamide antibiotics are one of the classes of antibiotics most associated with pseudomembranous colitis caused by Clostridium difficile.

Resistance: increased antibiotic use leads to the development of resistance. Two of the most common routes of resistance to lincosamides include Antibiotic modification, a route more prevalent in pathogenic gram-positive cocci, Organisms employing the antibiotic modification strategy inactivate lincosamides via adenylylation catalyzed by enzymes encoded by lin genes. These enzymes show amino acid sequence homology with the aminoglycoside antibiotic nucleotidyltransferase Methylation of the ribosomal 23S rRNA by Erm methyltransferases, observed in many genera and resulting in co resistance to macrolide and type B streptogramin antibiotics. Lincomycin : is used for treating serious bacterial infections caused by susceptible strains of streptococci, pneumococci, and staphylococci. Use of lincomycin is reserved for penicillin-allergic patients or when penicillin-based treatment is not appropriate. This antibiotic should only be used to treat serious infections because of rare but sometimes fatal intestinal problems have occurred (pseudomembranous colitis). Other  Side effects of lincomycin are:nausea,vomiting,diarrhea,abdominal pain,rash, and itching.  

  Clindamycin : is frequently used to treat infections caused by streptococci and staphylococci . Clindamycin treatments have been limited in the past because of rapid development of resistance and gastrointestinal side effects. Recently, as the emergence of multidrug-resistant pathogens has become a grave concern, lincosamide use has been revisited. In particular, clindamycin has been found to be potent in treating methicillin-resistant Staphylococcus aureus (MRSA), a pathogen causing worldwide concern because of its increasing rate of incidence and limited treatments .This drug is available in many forms. It comes as an oral capsule, oral solution, topical foam, topical gel, topical lotion, topical swab, topical solution, vaginal suppository, and vaginal cream. It’s also available as an intravenous (IV) drug Common side effects include nausea, diarrhea, rash, and pain at the site of injection. It increases the risk of hospital-acquired Clostridium difficile colitis about fourfold Clindamycin is used primarily to treat anaerobic infections caused by susceptible anaerobicbacteria, including dental infections, and infections of the respiratory tract, skin, and soft tissue In people with hypersensitivity to penicillins, clindamycin may be used to treat infections caused by susceptible aerobic bacteria, as well. It is also used to treat bone and joint infections, particularly those caused by Staphylococcus aureus.Topical application of clindamycin phosphate can be used to treat mild to moderate acne.افضل علاج لحاله حب الشباب Acne The use of clindamycin in conjunction with benzoyl peroxide is more effective in the treatment of acne than the use of either product by itself.

D-Test When testing a Gram-positive culture for sensitivity to clindamycin, it is common to perform a "D-Test" to determine if there is a macrolide-resistant sub-population of  bacteria present. This test is necessary because some bacteria express a phenotype known as MLSB, [Macrolide-lincosamide-streptogramin B resistance phenotypes in clinical Staphylococcus isolates] in which susceptibility tests will indicate the bacteria are susceptible to clindamycin, but in vitro the pathogen displays inducible resistance. To perform a D-test, an agar plate is inoculated with the bacteria in question and two drug-impregnated disks (one with erythromycin, one with clindamycin) are placed 15–20 mm apart on the plate. If the area of inhibition around the clindamycin disk is "D" shaped, the test result is positive and clindamycin should not be used due to the possibility of resistant pathogens  and therapy failure. If the area of inhibition around the clindamycin disk is circular, the test result is negative and clindamycin can be used

Streptogramins The streptogramin antibiotics were identified almost 50 years ago, but have only recently found clinical use as a consequence of the increase in multidrug-resistant bacteria irreversibly  bind to the 50S ribosomal subunit.  Group A streptogramins prevent peptide bond formation during chain elongation step, while group B components cause the release of incomplete peptide chains from the 50S ribosomal subunit. Streptogramins are effective in the treatment of vancomycin-resistant Staphylococcus aureus (VRSA) and vancomycin-resistant Enterococcus (VRE), two of the most rapidly growing strains of multidrug-resistant bacteria. They fall into two groups: streptogramin A and streptogramin B. Streptogramin is used in the treatment of respiratory tract infections Streptogramins A and B synergically inhibit cell growth of gram positive, less so gram negative bacteria by inhibiting protein synthesis, but separately they are bacteriostatic. The molecular target of streptogramins is the 23S rRNA. Both streptogramin A and B bind to the P binding site of the 50S ribosome subunit. The type A streptogramin binding causes a conformational change to the 50S subunit, which increases the activity of the type B streptogramin by a 100-fold. Streptogramin B prevents the elongation of protein chains and causes the release of incomplete peptides