Izano E A, Wang H, Ragunath C, Ramasubbu N, Kaplan J B
Department of Oral Biology, New Jersey Dental School, Medical Science Building, Newark, NJ 07103, USA.
J Dent Res. 2007 Jul;86(7):618-22. doi: 10.1177/154405910708600707.
The periodontopathogen Aggregatibacter actinomycetemcomitans forms tenacious biofilms on abiotic surfaces in vitro. The objective of the present study was to measure the susceptibility of A. actinomycetemcomitans biofilms to detachment and killing by the anionic surfactant sodium dodecyl sulfate (SDS). We found that biofilms formed by a wild-type strain were resistant to detachment by SDS. In contrast, biofilms formed by an isogenic mutant strain that was deficient in the production of PGA (poly-N-acetyl-glucosamine), a biofilm matrix polysaccharide, were sensitive to detachment by SDS. Pre-treatment of wild-type biofilms with dispersin B, a PGA-degrading enzyme, rendered them sensitive to detachment by SDS and resulted in a > 99% increase in SDS-mediated cell killing. We concluded that PGA protects A. actinomycetemcomitans cells from detachment and killing by SDS. Dispersin B and SDS may be useful agents for treating chronic infections caused by A. actinomycetemcomitans and other PGA-producing bacteria.
牙周病原体伴放线聚集杆菌在体外的非生物表面形成坚韧的生物膜。本研究的目的是测定伴放线聚集杆菌生物膜对阴离子表面活性剂十二烷基硫酸钠（SDS）的 detachment 和杀灭的敏感性。我们发现，野生型菌株形成的生物膜对 SDS 的 detachment 具有抗性。相比之下，由缺乏生物膜基质多糖 PGA（聚 - N - 乙酰 - 葡糖胺）产生的同基因突变菌株形成的生物膜对 SDS 的 detachment 敏感。用 PGA 降解酶分散素 B 预处理野生型生物膜，使其对 SDS 的 detachment 敏感，并导致 SDS 介导的细胞杀伤增加>99%。我们得出结论，PGA 保护伴放线聚集杆菌细胞免受 SDS 的 detachment 和杀灭。分散素 B 和 SDS 可能是治疗由伴放线聚集杆菌和其他产生 PGA 的细菌引起的慢性感染的有用药物。
