Cepacian degrading Cytobacillus sp. strain Dbc1 with anti-biofilm activity potentiating antibiotic efficacy against Burkholderia cepacia biofilm development

Abstract

Aim: Inhibition of biofilm formation in Burkholderia cepacia through enzymatic degradation of predominant exopolysaccharide (cepacian) of B. cepacia. Methodology: Cepacian was extracted from B. cepacia followed by isolation and identification of potent cepacian utilizing bacteria based on planktonic growth using cepacian as sole carbon source. Effective lyase activity (responsible for cepacian breakdown) and anti-biofilm activity of potent isolate against B. cepacia was determined. Effect of biofilm disintegration on antibiotic penetration into biofilm was detected. Lastly, inhibition of biofilm formation by crude lyase preparation of the isolate inside an external medical device was detected. Results: Cytobacillus sp. strain Dbc1 was the most potent cepacian degrading bacteria which showed significant lyase activity and reduced total biomass of both newly formed and pre-formed biofilm of B. cepacia. Cepacian degradation potentiated chloramphenicol penetration within pre-formed biofilm leading to cell mortality in B. cepacia. Cytobacillus sp. strain Dbc1significantly reduced total biomass of established biofilm inside nasal oxygen catheter. Interpretation: It can be concluded that Cytobacillus sp. strain Dbc1 significantly controlled mature B. cepacia biofilm through potent cepacian degrading and anti-biofilm activity along with better antibiotic targeting into established biofilm. Strain Dbc1 can be used to inhibit medical device- associated biofilms in vitro. Key words: Antibiotic susceptibility, Biofilm inhibition, Burkholderia cepacia, Cepacian breakdown, Multi-drug resistance