Machado Idalina, Graça Joana, Lopes Hélder, Lopes Susana, Pereira Maria O
Centre of Biological Engineering, Institute for Biotechnology and Bioengineering (IBB), University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal.
ISRN Biotechnol. 2012 Aug 28;2013:178646. doi: 10.5402/2013/178646. eCollection 2013.
This work aims at characterizing endoscope biofilm-isolated (PAI) and reference strain P. aeruginosa (PA) adhesion, biofilm formation and sensitivity to antibiotics. The recovery ability of the biofilm-growing bacteria subjected to intermittent antibiotic pressure (ciprofloxacin (CIP) and gentamicin (GM)), as well as the development of resistance towards antibiotics and benzalkonium chloride (BC), were also determined. The capacity of both strains to develop biofilms was greatly impaired in the presence of CIP and GM. Sanitization was not complete allowing biofilm recovery after the intermittent cycles of antibiotic pressure. The environmental pressure exerted by CIP and GM did not develop P. aeruginosa resistance to antibiotics nor cross-resistance towards BC. However, data highlighted that none of the antimicrobials led to complete biofilm eradication, allowing the recovery of the remaining adhered population possibly due to the selection of persister cells. This feature may lead to biofilm recalcitrance, reinforcement of bacterial attachment, and recolonization of other sites.
本研究旨在表征从内窥镜生物膜中分离出的铜绿假单胞菌（PAI）和参考菌株铜绿假单胞菌（PA）的黏附、生物膜形成及对抗生素的敏感性。还测定了经受间歇性抗生素压力（环丙沙星（CIP）和庆大霉素（GM））的生物膜生长细菌的恢复能力，以及对抗生素和苯扎氯铵（BC）的耐药性发展情况。在CIP和GM存在的情况下，两种菌株形成生物膜的能力均受到极大损害。消毒并不彻底，在抗生素压力的间歇性循环后生物膜仍可恢复。CIP和GM施加的环境压力并未使铜绿假单胞菌产生抗生素耐药性，也未产生对BC的交叉耐药性。然而，数据表明，没有一种抗菌剂能导致生物膜被完全根除，剩余黏附菌可能由于持留菌的选择而得以恢复。这一特性可能导致生物膜顽固性、细菌黏附增强以及在其他部位的重新定殖。
