## 2 Results and Discussion
### Effect of Acrylate Surface on Marine Bacteria  
Bacteria participate in the first irreversible phase of the microfouling process, which usually is involved in the subsequent attachment of bigger organisms, responsible for the macrofouling process [30,31]. In certain cases, the presence of biofilm can facilitate or inhibit the settlement of macroorganisms [32,33]. Therefore the control of bacterial adhesion and biofilm formation is usually considered a prerequisite for the control of biofouling. Furthermore, microfouling development on metallic structures can influence the deterioration of metal by micro-organism activity, thus causing microbially-influenced corrosion [34,35,36].  
In an earlier work [18], natural rubber-based coatings demonstrated AF activity against five species of marine bacteria, _Pseudoalteromonas elyakovii_, _Polaribacter irgensii_, _Cobetica marina_, _Shewanella putrefaciens_, and the pathogen _Vibrio aestuarianus_. These species, representative of microfouling agents in estuarine and marine environments, were provided by the ATCC collection. The determination of the AF activity was made using the inhibition halo method. To confirm this AF effect, for the present work, a new series of experiments were run using the colony count method [16], and wild bacterial strains, collected either from an intertidal mudflat biofilm, or associated with the corrosion products formed on carbon steel structures [37]. Among these bacteria, the _Shewanella_, _Alteromonas_ and _Vibrio splendidus_ strains belong to the _Gammaproteobacteria_ class, which may account, in association with _Alphaproteobacteria_, for 75% of commonly cultured bacteria from the marine environment [38]. _Gamma_- and _Alphaproteobacteriaacteria_ were recognized as the pioneering organisms in marine biofilm formation, especially _Ateromonas, Vibrio_, _Pseudomonas_ and _Pseudoalteromonas_[39,40,41]. _Vibrio_ strains were also detected with molecular methods as dominant bacteria inside corroding marine biofilms formed on carbon steel surfaces [42], suggesting their involvement in the biocorrosion processes. Similarly, _Bacillus_ was a commonly identified genus among culturable bacteria associated with the corrosion product layer during the early stages of marine corrosion of carbon steel. _Bacillus_ was also described as the dominant culturable chemoorganotrophic bacteria from planktonic communities of estuarine and marine environments [43] and was largely associated with microfouling on ship hull [44]. The _Flavobacterium_ class, which contains the _Flavobacterium_ strain, is also common in marine sediments [45] or in coastal water [46,47].  
The antifouling effect of the polyisoprene surfaces was species-dependent (Figure 6), as the adhesion of all species was reduced with the exception of _Flavobacterium_ II2003. In addition, _Flavobacterium_ was recently identified among the dominant bacteria growing on different commercial biocidal fouling control coatings [48]. _Bacillus_ IV3004 (Gram-positive) and _Shewanella_ IV3014 (Gram-negative) were very sensitive to acrylate surfaces and presented almost complete inhibition of adhesion and growth on the surfaces. The AF mechanism of action of the surfaces did not seem related to the type of cell wall.