Sparo M D, Jones D G, Sánchez Bruni S F
Parasitology Division, Moredun Research Institute, Penicuik, UK.
Chemotherapy. 2009;55(4):270-7. doi: 10.1159/000223069. Epub 2009 Jun 2.
Resistant Gram-positive bacteria are causing increasing concern in clinical practice. This work investigated the efficacy of AP-CECT7121 (an antimicrobial peptide isolated from an environmental strain of Enterococcus faecalis CECT7121) against various pathogenic Gram-positive bacteria.
Strains were isolated from intensive care unit patients unresponsive to standard antibiotic treatments. Inhibitory activity of AP-CECT7121 was assessed using the agar-well diffusion method. The most resistant isolates from each species screened (Enterococcus faecium, Enterococcus faecalis,Staphylococcus aureus, Streptococcus pneumoniae, Streptococcus pyogenes, Clostridium perfringens and Clostridium difficile) were further examined in time-killing curve studies.
These bactericidal kinetic experiments demonstrated a rapid killing effect with no viable bacteria being detected within 30 and 90 min for enterococcal and streptococcal strains and 180 min for community-acquired methicillin-resistant S. aureus and C. perfringens: viable counts for C. difficile were threefold decreased after 90 min.
AP-CECT7121 may provide a novel strategy for treating potentially fatal clinical infections in hospitalized patients.
耐革兰氏阳性菌在临床实践中日益引起关注。本研究调查了AP - CECT7121（一种从粪肠球菌环境菌株CECT7121中分离出的抗菌肽）对各种致病性革兰氏阳性菌的疗效。
从对标准抗生素治疗无反应的重症监护病房患者中分离菌株。采用琼脂孔扩散法评估AP - CECT7121的抑制活性。对筛选出的每种细菌（屎肠球菌、粪肠球菌、金黄色葡萄球菌、肺炎链球菌、化脓性链球菌、产气荚膜梭菌和艰难梭菌）中耐药性最强的分离株进行时间 - 杀菌曲线研究。
这些杀菌动力学实验表明，对于肠球菌和链球菌菌株，在30分钟和90分钟内未检测到活菌，对于社区获得性耐甲氧西林金黄色葡萄球菌和气荚膜梭菌，在180分钟内未检测到活菌，呈现出快速杀菌效果：艰难梭菌的活菌数在90分钟后减少了三倍。
AP - CECT7121可能为治疗住院患者潜在致命的临床感染提供一种新策略。
