MRSA and MSSA: The Mechanism of Methicillin Resistance and the Influence of Methicillin Resistance on Biofilm Phenotype of Staphylococcus aureus

Abstract

Staphylococcus aureus (S. aureus), which is one of the most common causes of indwelling device-associated, nosocomial, and community-acquired infections, can produce bioilm as a virulence factor. Methicillin-resistant S. aureus (MRSA) that is resistant to β-lactam antibiotics causes life-threatening infections. Bioilm producer strains of S. aureus that causes indwelling device-associated infections resist to antimicrobials and immune system. The combination of methicillin resistance and the ability of bioilm formation of S. aureus makes treatment diicult. Methicillin resistance of S. aureus can afect bioilm phenotype of S. aureus; the mecA gene of MRSA increases bioilm production by inactivating accessory gene regulator (agr) quorum sensing regulator system, which is a two-component regulator system of virulence factor production. The aim of this review is to determine virulence factors of S. aureus, resistance mechanisms of methicillin, and the inluence of methicillin resistance on bioilm phenotype of S. aureus. Keywords:Staphylococcus aureus, MRSA, MSSA, bioilm, methicillin resistance, virulence, inluence of methicillin resistance on bioilm IntroductionThe bioilm has an important role in the pathogenesis of certain bacterial infections such as staphylococcal indwelling device-associated infections, wound infections, chronic urinary tract infections (UTI), cystic ibrosis pneumonia, chronic otitis media (OM), chronic rhinosinusitis, periodontitis, and recurrent tonsillitis [1].© 2017 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.© 2017 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.The bioilm infections such as Staphylococcus aureus (S. aureus) infections are the important problems in hospitalized and immunosuppressed patients worldwide due to their tough and nonresponsive treatment by antibiotics. Bioilm-producing bacteria are resistant to immune defense, antibiotics, and many antimicrobial agents [2,3].The mecA gene, which is located in the staphylococcal chromosomes, enhances virulence of Staphylococcus by causing resistant to methicillin antibiotics. Methicillin-resistant S. aureus (MRSA) causes hospital-associated (HA-MRSA) and community-associated (CA-MRSA) infections. Methicillin resistance of S. aureus causes treatment of S. aureus tough by antibiotics due to its resistance to all β-lactam antibiotics. Mechanisms of resistance to β-lactam antibiotics such as methicillin are regulated by regulatory genes in the presence of such antibiotics. S. aureus bioilm formation is regulated globally by the accessory gene regulator (...

Characteristics of antibiotic sensitivity of Staphylococcus aureus isolated from dairy farms in Ukraine

“…Similar to studies of other authors from different regions of the world, the highest rate of resistance was detected for β-lactam antibiotics. The resistance to other tested agents was less common, which is also in agreement with the general trend observed worldwide (Li et al, 2009;Abebe et al, 2016;Kirmusaoglu, 2017).…”

“…Secondly, S. aureus can survive and persist in these objects for a long time and contaminate raw milk again. Few researchers have published information about biofilm formation by S. aureus on dairy equipment, from which bacteria penetrate raw milk, reducing the time of its shelf life and also cause poisoning of consumers (Kirmusaoglu, 2017;.…”

Introductory Chapter: The Action Mechanisms of Antibiotics and Antibiotic Resistance

“…Targets of antimicrobials are cell membrane, cell wall, protein synthesis, nucleic acid synthesis, and biological metabolic compound synthesis ( Figure 1) [2]. Over usage of antibiotics, mutations in the genes, carrying resistance genes in chromosomes and plasmids, gaining resistance genes carried by transposons, insertion sequences (IS) and conjugation from the same or other species of microorganisms cause bacteria develop resistance to antimicrobials [3].…”

“…After bactoprenol, which is a membrane-bound acceptor, transfers UDP-NAMpentapeptide and UDP-NAG from cytoplasm to outer site of cell membrane, transglycosylation, and transpeptidation reactions are catalyzed by penicillinbinding proteins (PBPs) bound to cell membrane as a DD-peptidases to construct peptidoglycan [3]. [4] (bnm MRSA and MSSA).…”

“…After this blockage of active site, intracellular zinc metalloprotease domain of BlaRI releases BlaI bound to blaI-blaRI operator. By upregulation of blaZ gene, βlactamase enzyme is synthesized, so the microorganism develops resistance to βlactam used [3].…”