性能描述

storage temp.   2-8°C

Biochem/physiol Actions
Cephalexin disrupts the synthesis of the peptidoglycan layer of bacterial cell walls which is responsible for cell wall structural integrity. Peptidoglycan synthesis is facilitated by transpeptidases known as penicillin-binding proteins (PBPs). PBPs bind to the D-Ala-D-Ala at the end of muropeptides (peptidoglycan precursors) to crosslink the peptidoglycan. Cephalexin antibiotics mimic the D-Ala-D-Ala site, thereby competitively inhibiting PBP crosslinking of peptidoglycan.

Application
Cephalexin is a cephalosporin antibiotic used to study the effect of expression, binding, and inhibition of PBP3 and other penicillin-binding proteins (PBPs) on bacterial cell wall mucopeptide synthesis.

说明：该品为白色或乳黄色结晶性粉末；微臭。该品在水中微溶，在乙醇、氯仿或乙醚中不溶。比旋度取该品，精密称定，加水溶解并稀释成每1ml中含5mg的溶液，依法测定，比旋度为+144度至+158度。吸收系数 取该品，精密 
称定，加水溶解并稀释成每1ml中约含20μg的溶液，照分光光度法，在262nm的波长处测定吸收度，吸收系数为220～245。