Nucleolytic enzymes from the marine bacterium Cobetia amphilecti KMM 296 with antibiofilm activity and biopreservative effect on meat products

Cultivation of Pseudomonas aeruginosa (P. aeruginosa), Bacillus subtilis (B.subtilis), Salmonella enterica (S. enterica), and Staphylococcus aureus (S. aureus) isolated from meat products together with the marine bacterium Cobetia amphilecti KMM 296 (Cobetia marina) resulted in inhibition of their cell growth and complete degradation of biofilms of P. aeruginosa and B. subtilis. The degradation patterns of their mature biofilms treated with Cobetia amphilecti (C. amphilecti) extracellular nucleolytic enzymes revealed that the highly active alkaline phosphatase CmAP could be a significant antibiofilm factor. Moreover, CmAP possessed strong dose-dependent inhibition effect on de novo biofilm formation by bacterial cells regardless of the species. The concentration of CmAP for exhibition of maximal effect on microbial growth and biofilms was 1.1 mu g/m1 with activity of 2.5 units/ml that diminished total aerobic mesophilic and lactic acid counts in sausage shells by 3.5 log units for 5 days and 2.5 log units for 6 days, respectively. The stabilized antifungal effect continued the same period of storage. The nuclease-like enzymes CmEEP and CmNUC were species-independent and largely degraded biofilms at lowered pH. The bio-preservative effect on meat products at low concentration and psychrophilicity of CmAP can be used for enzymatic cleaning of surfaces in food industry. (C) 2017 Published by Elsevier Ltd.