Cardiac Output, Venous Return, and Their Regulation
ย
Bc2 antibiotic resistance group4
1. Mechanisms of Methicillin Resistance
in Staphylococcus aureus
Group 4:
Vรต ฤแป Minh Trang
Nguyแป n Thแป Hแปng Nhung
Lรฝ Minh Nguyแปt
Nguyแป n Lรช Bแบฃo Trรขn
ฤoร n Ngแปc Thแบฃo Vy
Phan Ngแปc Mai Vy
2. Mechanism Methicillin resist
to Stap.
โ Methicillin is A semisynthetic penicillin-related antibiotic
โ Beta-lactams bind to penicillin-binding proteins (PBPs)
โ essential for cell membrane biosynthesis and prevent peptidoglycan cross-
linking
โ leading to bacterial cell lysis.
3. Mechanism Stap. resist to
Methicillin
MRSA is Methicillin-resistant Staphylococcus aureus
*Resistance to MRSA beta-lactams:
+ acquired genetic predisposition
+ staphylococcal cassette chromosome (SCCmecs) carrying the mec A gene
encoding the modified PBP - PBP2a
+ PBP2a is encoded by the mecA gene, carried on a distinct mobile genetic
element (SCCmec), the expression of which is controlled through a
proteolytic signal transduction pathway comprising a sensor protein
(MecR1) and a repressor (MecI)
โ Reduced affinity resistance to beta-lactam antibiotics.
4.
5. Mechanism Stap. resist to
Methicillin
โ Consequently, at therapeutic levels of methicillin that would
inhibit the activities of other PBPs
โ However, the MRSA bacteria still countinuos the formation of
membrane biosynthesis
=> PBP2a remains active ensuring the cross-linking of the glycan
chains in peptidoglycan.
6. References:
1. Peacock SJ, Paterson GK. Mechanisms of Methicillin Resistance in Staphylococcus aureus. Annu Rev Biochem.
2015;84:577-601. doi: 10.1146/annurev-biochem-060614-034516. PMID: 26034890.
2. Lee AS, de Lencastre H, Garau J, Kluytmans J, Malhotra-Kumar S, Peschel A, Harbarth S. Methicillin-resistant
Staphylococcus aureus. Nat Rev Dis Primers. 2018 May 31;4:18033. doi: 10.1038/nrdp.2018.33. PMID: 29849094.
3. http://www.hoihohaptphcm.org/chuyende/benh-phoi/341-tong-quan-tu-cau-khang-methicillin
4. https://www.seattlechildrens.org/pdf/PE485V.pdf
