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Compounds from silicones alter enzyme activity in curing barnacle glue and model enzymes.

Rittschof D, Orihuela B, Harder T, Stafslien S, Chisholm B, Dickinson GH - PLoS ONE (2011)

Bottom Line: Mixtures of compounds were found on 2 commercial and 8 model silicone coatings.Activity of purified trypsin and, to a greater extent, transglutaminase was significantly altered by relevant concentrations of silicone polymer constituents.Surface-associated silicone compounds can disrupt glue curing and alter enzyme properties.

View Article: PubMed Central - PubMed

Affiliation: MSC Division, Duke University Marine Laboratory, Nicholas School of the Environment, Beaufort, North Carolina, United States of America. ritt@duke.edu

ABSTRACT

Background: Attachment strength of fouling organisms on silicone coatings is low. We hypothesized that low attachment strength on silicones is, in part, due to the interaction of surface available components with natural glues. Components could alter curing of glues through bulk changes or specifically through altered enzyme activity.

Methodology/principal findings: GC-MS analysis of silicone coatings showed surface-available siloxanes when the coatings were gently rubbed with a cotton swab for 15 seconds or given a 30 second rinse with methanol. Mixtures of compounds were found on 2 commercial and 8 model silicone coatings. The hypothesis that silicone components alter glue curing enzymes was tested with curing barnacle glue and with commercial enzymes. In our model, barnacle glue curing involves trypsin-like serine protease(s), which activate enzymes and structural proteins, and a transglutaminase which cross-links glue proteins. Transglutaminase activity was significantly altered upon exposure of curing glue from individual barnacles to silicone eluates. Activity of purified trypsin and, to a greater extent, transglutaminase was significantly altered by relevant concentrations of silicone polymer constituents.

Conclusions/significance: Surface-associated silicone compounds can disrupt glue curing and alter enzyme properties. Altered curing of natural glues has potential in fouling management.

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Related in: MedlinePlus

Effect of silicone oil and PDMS oligomers on purified trypsin and transglutaminase activity from porcine and guinea pig, respectively.Silicone oil (viscosity 40–50 cSt) and low, medium and high molecular weight PDMS oligomers (viscosity 700–800, 1000, and 5000 cSt respectively) were tested alone and in combination. Components were dissolved in methanol, the methanol was then dried completely, and residual was resuspended directly in assay buffer. Data are expressed as percent change in OD405 (trypsin) or OD450 (transglutaminase) from control. Means and SEM are shown. The control is purified enzyme incubated with assay buffer only, without silicone components. * Indicates a significant difference from control (Dunn's method post-hoc analysis: p<0.05). n = 10 replicates for individual components, 5 replicates for combinations.
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pone-0016487-g007: Effect of silicone oil and PDMS oligomers on purified trypsin and transglutaminase activity from porcine and guinea pig, respectively.Silicone oil (viscosity 40–50 cSt) and low, medium and high molecular weight PDMS oligomers (viscosity 700–800, 1000, and 5000 cSt respectively) were tested alone and in combination. Components were dissolved in methanol, the methanol was then dried completely, and residual was resuspended directly in assay buffer. Data are expressed as percent change in OD405 (trypsin) or OD450 (transglutaminase) from control. Means and SEM are shown. The control is purified enzyme incubated with assay buffer only, without silicone components. * Indicates a significant difference from control (Dunn's method post-hoc analysis: p<0.05). n = 10 replicates for individual components, 5 replicates for combinations.

Mentions: The components of model polysiloxane coatings that alter enzyme activity were determined using commercial trypsin and transglutaminase (Figure 7). Components were tested individually and in combination, and included silicone oil, and low, medium and high molecular weight PDMS oligomers. The controls for these assays were purified enzymes incubated without silicone components. Non-parametric analyses were employed for these comparisons, since data did not meet assumptions of normality and equality.


Compounds from silicones alter enzyme activity in curing barnacle glue and model enzymes.

Rittschof D, Orihuela B, Harder T, Stafslien S, Chisholm B, Dickinson GH - PLoS ONE (2011)

Effect of silicone oil and PDMS oligomers on purified trypsin and transglutaminase activity from porcine and guinea pig, respectively.Silicone oil (viscosity 40–50 cSt) and low, medium and high molecular weight PDMS oligomers (viscosity 700–800, 1000, and 5000 cSt respectively) were tested alone and in combination. Components were dissolved in methanol, the methanol was then dried completely, and residual was resuspended directly in assay buffer. Data are expressed as percent change in OD405 (trypsin) or OD450 (transglutaminase) from control. Means and SEM are shown. The control is purified enzyme incubated with assay buffer only, without silicone components. * Indicates a significant difference from control (Dunn's method post-hoc analysis: p<0.05). n = 10 replicates for individual components, 5 replicates for combinations.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3040736&req=5

pone-0016487-g007: Effect of silicone oil and PDMS oligomers on purified trypsin and transglutaminase activity from porcine and guinea pig, respectively.Silicone oil (viscosity 40–50 cSt) and low, medium and high molecular weight PDMS oligomers (viscosity 700–800, 1000, and 5000 cSt respectively) were tested alone and in combination. Components were dissolved in methanol, the methanol was then dried completely, and residual was resuspended directly in assay buffer. Data are expressed as percent change in OD405 (trypsin) or OD450 (transglutaminase) from control. Means and SEM are shown. The control is purified enzyme incubated with assay buffer only, without silicone components. * Indicates a significant difference from control (Dunn's method post-hoc analysis: p<0.05). n = 10 replicates for individual components, 5 replicates for combinations.
Mentions: The components of model polysiloxane coatings that alter enzyme activity were determined using commercial trypsin and transglutaminase (Figure 7). Components were tested individually and in combination, and included silicone oil, and low, medium and high molecular weight PDMS oligomers. The controls for these assays were purified enzymes incubated without silicone components. Non-parametric analyses were employed for these comparisons, since data did not meet assumptions of normality and equality.

Bottom Line: Mixtures of compounds were found on 2 commercial and 8 model silicone coatings.Activity of purified trypsin and, to a greater extent, transglutaminase was significantly altered by relevant concentrations of silicone polymer constituents.Surface-associated silicone compounds can disrupt glue curing and alter enzyme properties.

View Article: PubMed Central - PubMed

Affiliation: MSC Division, Duke University Marine Laboratory, Nicholas School of the Environment, Beaufort, North Carolina, United States of America. ritt@duke.edu

ABSTRACT

Background: Attachment strength of fouling organisms on silicone coatings is low. We hypothesized that low attachment strength on silicones is, in part, due to the interaction of surface available components with natural glues. Components could alter curing of glues through bulk changes or specifically through altered enzyme activity.

Methodology/principal findings: GC-MS analysis of silicone coatings showed surface-available siloxanes when the coatings were gently rubbed with a cotton swab for 15 seconds or given a 30 second rinse with methanol. Mixtures of compounds were found on 2 commercial and 8 model silicone coatings. The hypothesis that silicone components alter glue curing enzymes was tested with curing barnacle glue and with commercial enzymes. In our model, barnacle glue curing involves trypsin-like serine protease(s), which activate enzymes and structural proteins, and a transglutaminase which cross-links glue proteins. Transglutaminase activity was significantly altered upon exposure of curing glue from individual barnacles to silicone eluates. Activity of purified trypsin and, to a greater extent, transglutaminase was significantly altered by relevant concentrations of silicone polymer constituents.

Conclusions/significance: Surface-associated silicone compounds can disrupt glue curing and alter enzyme properties. Altered curing of natural glues has potential in fouling management.

Show MeSH
Related in: MedlinePlus