Antibiofilm activity of Cobetia marina filtrate upon Staphylococcus epidermidis catheter-related isolates

Abstract

We report the antibiofilm activity by the sponge-associated bacterium Cobetia marina upon Staphylococcus epidermidis clinical isolates obtained from central venous catheters. Antibiofilm activity/antimicrobial susceptibility correlation might predict the action of the metabolite(s) upon Staphylococcus epidermidis in the clinic, making it a possible adjuvant in therapies against biofilm-associated infections.Key words: biofilms, antibiofilm activity, Staphylococcus epidermidis, Cobetia marina, Darwinella sp.Medical device-related infections represent a serious clinical problem, since the majority of hospital patients undergo procedures for the insertion of foreign devices. Indeed, staphylococcal implant-related infections are the prototype of a biofilm infection and coagulase-negative staphylococci, mainly Staphylococcus epidermidis, predominate as the agent of these biomedical infections (11,12). Once the biofilm is established, therapeutic options become limited due to difficulties with the perfusion of antimicrobial agents into biofilm and to the metabolic latent state of bacteria in the biofilm lifestyle. Thus, interference with cell-cell signaling by modulating quorum sensing (QS) to prevent biofilm formation might be an attractive strategy to treat these infections. In this alternative approach, which does not interfere with bacterial growth, the switching off of virulence expression and attenuation of the pathogen make microorganisms more susceptible to antimicrobials and to the immune system (9).The potential advantages of antivirulence therapies include the large number of bacterial functions that can be inhibited, the preservation of normal human microbiota and the reduction in selective pressure that may result in decreased resistance (4).Marine sponges are reservoirs of microorganisms and their survival in this particular environment resulted in the ability to produce unique compounds as a manner of combating enemies (16), an ability which we wanted to exploit in order to target pathogenic biofilms. To our knowledge this is the first report on the production of culture filtrate obtained from the marine Gramnegative bacterium Cobetia marina, which interferes significantly in S. epidermidis biofilm formation.

Antibiofilm activity of natural substances derived from plants

“…Extracts of Bauhinia acuruana and Pityrocarpa moniliformis presented biofilm inhibitory activity for the same microorganism, without causing bacterial death (Trentin et al, 2011a, b).…”

“…Various streptococcus infections, specially chronic infection, might be related to the formation of bacteria in biofilms (Al-Dhabi et al, 2012). The development of biofilms grants high resistance to the microorganisms, due to their involution in a matrix of extracellular polymeric substances, forming a barrier which stops or hampers the diffusion of antimicrobial substances through the colony (Trentin et al, 2011a, b). The ideal form of avoiding their action in pathogenic processes is to stop their development (Rozalski et al, 2013) in order to do that, the investment in the search of products and methods that interfere with the bacterial accumulation through adhesion control, inhibition of interbacterial communication or the establishment of the polysaccharidic matrix is needed (Jakubovics and Kolenbrander, 2010).…”

“…Synergetic studies have shown that the addition of hop compounds decreased the value of MIC for commercial antibiotics oxacillin and linezolide from 0.125 and 0.5 to 0.094 and 0.38 μg/mL, respectively (Rozalski et al, 2013). Trentin et al (2011a, b) conducted a study on the effect of the filtrate of a Cobetia marina colony, a Gramnegative marine bacterium, on the formation of biofilm in S. epidermidis, an important agent in hospital-acquired infections. The filtrate does not possess the capacity of destructing consolidated biofilm; however, it inhibited its formation in 84.7%.…”

Complete genome sequencing and comparison of two nitrogen-metabolizing bacteria isolated from Antarctic deep-sea sediment

“…The genus is characterized by GRAM-negative, straight, rod-shaped cells of 1.6–4.0 by 0.8–1.2 µm that occur singly and in pairs [ 1 ]. Some reports have also revealed that members of the genus Cobetia are promising sources of unique enzymes and secondary metabolites, can produce an alkaline phosphatase with unusually high specific activity [ 2 , 3 ], can synthesize hydroxyectoine under NaCl induction and are tolerant to osmotic stress [ 4 ], and have antibiofilm activity [ 5 ]. Due to their 16S rRNA sequences with high homology, Noskova suggested that gene-specific oligonucleotides corresponding to the coding sequences for factors with vital bacterial cell functions, such as the alkaline phosphatases PhoA and PhoD may be used for the rapid molecular differentiation of closely related species of the marine bacterial genus Cobetia [ 6 ].…”

Biofilm formation by Xanthomonas campestris pv. viticola affected by abiotic surfaces and culture media

“…Sterile, flat-bottom, 96-well polystyrene microtiter plates (Costar 3599 Corning Inc.) were used to evaluate biofilm formation according to a protocol adapted from Trentin et al (2011). Each well was filled with 140 μL of culture medium, 20 μL of Milli-Q water, and 40 μL of bacterial suspension (3 × 10 8 CFU/mL).…”