Department of Surgery, Duke University Medical Center, Durham, North Carolina 27710, USA.
Microbiol Immunol. 2011 Mar;55(3):174-83. doi: 10.1111/j.1348-0421.2010.00297.x.
Extracellular matrices utilized by biofilms growing on inert surfaces are generally produced entirely by the bacteria growing within those biofilms, whereas symbiotic (mutualistic) biofilms growing in or on a wide range of plants and animals utilize host-derived macromolecules, such as mucoid substances, as components of their extracellular matrix. Incorporation of host-derived molecules may have a profound effect on the resistance to antibiotics of symbiotic biofilms, which may have important implications for medicine and biology. As an initial probe of the potential effects of host-derived molecules in the extracellular matrix on the sensitivity of biofilms to antibiotics, an in vitro model was used to evaluate the effects of ciprofloxacin on biofilms grown in the presence and absence of SIgA, a host-derived glycoprotein associated with biofilms in the mammalian gut. In five out of six strains of Escherichia coli tested, the incorporation of SIgA into the biofilms apparently reduced the resistance of the bacteria to ciprofloxacin. On the other hand, SIgA generally increased the resistance of planktonic bacteria to ciprofloxacin, perhaps due in part to the SIgA-mediated aggregation of the bacteria. These findings suggest that incorporation of host-derived molecules into the extracellular matrix of symbiotic biofilms might profoundly alter the properties of those biofilms, including the resistance of those biofilms to antibiotics.
在惰性表面上生长的生物膜所利用的细胞外基质通常完全由生长在这些生物膜内的细菌产生，而在广泛的动植物中生长的共生（互利共生）生物膜则利用宿主来源的大分子，如黏液物质，作为其细胞外基质的成分。宿主来源分子的掺入可能对共生生物膜对抗生素的耐药性产生深远影响，这可能对医学和生物学具有重要意义。作为宿主来源分子在细胞外基质中对生物膜对抗生素敏感性的潜在影响的初步探讨，使用体外模型评估了在存在和不存在与哺乳动物肠道生物膜相关的宿主来源糖蛋白 SIgA 的情况下，环丙沙星对生物膜生长的影响。在测试的六种大肠杆菌菌株中的五种中，将 SIgA 掺入生物膜中显然降低了细菌对环丙沙星的耐药性。另一方面，SIgA 通常会增加浮游细菌对环丙沙星的耐药性，这可能部分归因于 SIgA 介导的细菌聚集。这些发现表明，宿主来源分子掺入共生生物膜的细胞外基质可能会深刻改变这些生物膜的特性，包括这些生物膜对抗生素的耐药性。
