Pseudoalteromonas spp. Serve as Initial Bacterial Attractants in Mesocosms of Coastal Waters but Have Subsequent Antifouling Capacity in Mesocosms and when Embedded in Paint

Abstract

The purpose of the present study was to determine if the monoculture antifouling effect of several pigmented pseudoalteromonads was retained in in vitro mesocosm systems using natural coastal seawater and when the bacteria were embedded in paint used on surfaces submerged in coastal waters. Pseudoalteromonas piscicida survived on a steel surface and retained antifouling activity for at least 53 days in sterile seawater, whereas P. tunicata survived and had antifouling activity for only 1 week. However, during the first week, all Pseudoalteromonas strains facilitated rather than prevented bacterial attachment when used to coat stainless steel surfaces and submerged in mesocosms with natural seawater. The bacterial density on surfaces coated with sterile growth medium was 10 5 cells/cm 2 after 7 days, whereas counts on surfaces precoated with Pseudoalteromonas were significantly higher, at 10 6 to 10 8 cells/cm 2 . However, after 53 days, seven of eight Pseudoalteromonas strains had reduced total bacterial adhesion compared to the control. P. piscicida, P. antarctica, and P. ulvae remained on the surface, at levels similar to those in the initial coating, whereas P. tunicata could not be detected. Larger fouling organisms were observed on all plates precoated with Pseudoalteromonas; however, plates coated only with sterile growth medium were dominated by a bacterial biofilm. Suspensions of a P. piscicida strain and a P. tunicata strain were incorporated into ship paints (Hempasil x3 87500 and Hempasil 77500) used on plates that were placed at the Hempel A/S test site in Jyllinge Harbor. For the first 4 months, no differences were observed between control plates and treated plates, but after 5 to 6 months, the control plates were more fouled than the plates with pseudoalteromonad-based paint. Our study demonstrates that no single laboratory assay can predict antifouling effects and that a combination of laboratory and real-life methods must be used to determine the potential antifouling capability of new agents or organisms.

Exposure to Crude Oil and Chemical Dispersant May Impact Marine Microbial Biofilm Composition and Steel Corrosion

“…Changes in the relative abundance of dominant OTUs over time are what distinguished biofilm and SW communities from each other. Notably, the dominant OTUs in biofilms and SW were affiliated with the Rhodobacteraceae family and the Pseudoalteromonas genus; both play important roles in marine biofilm formation (Dang and Lovell, 2000, 2002Dang et al, 2008;Iijima et al, 2009;Bernbom et al, 2013;Elifantz et al, 2013).…”

Evaluation of cationic micropeptides derived from the innate immune system as inhibitors of marine biofouling

“…The current investigation represents the first study of the effects of compounds initially derived from the innate immune system on marine biofouling and on organisms in a marine setting, and extends recent studies towards biofilms (Ammons & Copie 2013;Alves & Olivia Pereira 2014). The complex biofouling scenario, in which several types of organisms are involved, is difficult to mimic in a single assay (Bernbom et al 2013) and it is necessary to include both micro-and macrofoulers in a study when assessing the complete potential AF properties of a compound (Qian et al 2010). The 19 different organisms included in the present investigation (18 microfoulers and the macrofouler Balanus improvisus) provide a comprehensive overview of the AF effect of the investigated peptides, both in terms of organism growth and surface adhesion .…”

Method for localizing and differentiating bacteria within biofilms grown on indium tin oxide : spatial distribution of exoelectrogenic bacteria within intact ITO biofilms via FISH

“…There was clearly a synergistic effect when the bacteria were grown together as a co-culture. Pseudomonads are known as primary biofilm colonizers and likely helped to facilitate the proliferation of S. oneidensis MR-1 (Dang and Lovell, 2000;Bernborn et al 2013).…”