a Department of Biochemistry , Central University of Rajasthan , Ajmer , India.
b Microbial Biofilm Laboratory, IRCCS Fondazione Santa Lucia , Rome , Italy.
Virulence. 2018 Jan 1;9(1):522-554. doi: 10.1080/21505594.2017.1313372.
Biofilm refers to the complex, sessile communities of microbes found either attached to a surface or buried firmly in an extracellular matrix as aggregates. The biofilm matrix surrounding bacteria makes them tolerant to harsh conditions and resistant to antibacterial treatments. Moreover, the biofilms are responsible for causing a broad range of chronic diseases and due to the emergence of antibiotic resistance in bacteria it has really become difficult to treat them with efficacy. Furthermore, the antibiotics available till date are ineffective for treating these biofilm related infections due to their higher values of minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC), which may result in in-vivo toxicity. Hence, it is critically important to design or screen anti-biofilm molecules that can effectively minimize and eradicate biofilm related infections. In the present article, we have highlighted the mechanism of biofilm formation with reference to different models and various methods used for biofilm detection. A major focus has been put on various anti-biofilm molecules discovered or tested till date which may include herbal active compounds, chelating agents, peptide antibiotics, lantibiotics and synthetic chemical compounds along with their structures, mechanism of action and their respective MICs, MBCs, minimum biofilm inhibitory concentrations (MBICs) as well as the half maximal inhibitory concentration (IC) values available in the literature so far. Different mode of action of anti biofilm molecules addressed here are inhibition via interference in the quorum sensing pathways, adhesion mechanism, disruption of extracellular DNA, protein, lipopolysaccharides, exopolysaccharides and secondary messengers involved in various signaling pathways. From this study, we conclude that the molecules considered here might be used to treat biofilm-associated infections after significant structural modifications, thereby investigating its effective delivery in the host. It should also be ensured that minimum effective concentration of these molecules must be capable of eradicating biofilm infections with maximum potency without posing any adverse side effects on the host.
生物膜是指存在于微生物的复杂、固着群落,这些微生物要么附着在表面上,要么牢固地埋在细胞外基质中作为聚集物。包围细菌的生物膜基质使它们能够耐受恶劣条件,并抵抗抗菌治疗。此外,生物膜是引起广泛慢性疾病的原因,并且由于细菌对抗生素的耐药性的出现,用疗效有效地治疗它们变得非常困难。此外,由于其最低抑菌浓度(MIC)和最低杀菌浓度(MBC)较高,目前可用的抗生素对治疗这些生物膜相关感染无效,这可能导致体内毒性。因此,设计或筛选能够有效减少和消除生物膜相关感染的抗生物膜分子至关重要。在本文中,我们参考不同的模型和用于生物膜检测的各种方法,强调了生物膜形成的机制。重点关注了迄今为止发现或测试过的各种抗生物膜分子,这些分子可能包括草药活性化合物、螯合剂、肽抗生素、类抗生素和合成化学化合物,以及它们的结构、作用机制以及各自的 MIC、MBC、最低生物膜抑制浓度(MBIC)以及迄今为止文献中可用的半最大抑制浓度(IC)值。本文讨论的抗生物膜分子的不同作用模式是通过干扰群体感应途径、粘附机制、破坏细胞外 DNA、蛋白质、脂多糖、胞外多糖和参与各种信号通路的二级信使来抑制。从这项研究中,我们得出结论,经过显著的结构修饰后,这里考虑的分子可能用于治疗与生物膜相关的感染,从而研究其在宿主中的有效传递。还应确保这些分子的最低有效浓度能够以最大效力根除生物膜感染,而不对宿主产生任何不利的副作用。