Reduced seawater pH alters marine biofilms with impacts for marine polychaete larval settlement

Abstract Larval settlement is a key process in the lifecycle of benthic marine organisms; however, little is known on how it could change in reduced seawater pH and carbonate saturation states under future ocean acidification (OA). This is important, as settlement ensures species occur in optimal environments and, for commercially important species such as abalone, reduced settlement could decrease future population success. We investigated how OA could affect settlement success in the New Zealand abalone Haliotis iris by examining: (1) direct effects of seawater at ambient (pHT 8.05) and reduced pHT (7.65) at the time of settlement, (2) indirect effects of settlement substrates (crustose coralline algae, CCA) preconditioned at ambient and reduced pHT for 171 days, and (3) carry-over effects, by examining settlement in larvae reared to competency at ambient and reduced pHT (7.80). We found no effects of seawater pH or CCA incubation on larval settlement success. OA-induced carry-over effects were evident, with lower settlement in larvae reared at reduced pH. Understanding the mechanisms behind these responses is key to fully comprehend the extent to which OA will affect marine organisms and the industries that rely on them.

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Love at First Taste: Induction of Larval Settlement by Marine Microbes

International Journal of Molecular Sciences ◽

10.3390/ijms21030731 ◽

2020 ◽

Vol 21 (3) ◽

pp. 731 ◽

Cited By ~ 10

Author(s):

Sergey Dobretsov ◽

Daniel Rittschof

Keyword(s):

Extracellular Polymeric Substances ◽

Degradation Products ◽

Meta Analysis ◽

Larval Settlement ◽

Structural Protein ◽

Unicellular Algae ◽

Marine Biofilms ◽

Settlement And Metamorphosis ◽

Molecular Aspects ◽

The Impact

Marine biofilms are composed of many species of bacteria, unicellular algae, and protozoa. Biofilms can induce, inhibit, or have no effect on settlement of larvae and spores of algae. In this review, we focus on induction of larval settlement by marine bacteria and unicellular eukaryotes and review publications from 2010 to September 2019. This review provides insights from meta-analysis on what is known about the effect of marine biofilms on larval settlement. Of great interest is the impact of different components of marine biofilms, such as bacteria and diatoms, extracellular polymeric substances, quorum sensing signals, unique inductive compounds, exoenzymes, and structural protein degradation products on larval settlement and metamorphosis. Molecular aspects of larval settlement and impact of climate change are reviewed and, finally, potential areas of future investigations are provided.

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The chemical nature of bacteria-derived larval settlement cue(s) for the marine polychaete hydroides elegans (Haswell)

10.14711/thesis-b710295 ◽

2001 ◽

Author(s):

Stanley Chun Kwan Lau

Keyword(s):

Chemical Nature ◽

Larval Settlement ◽

Hydroides Elegans ◽

Marine Polychaete

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Discovery of Antibiofilm Activity of Elasnin against Marine Biofilms and Its Application in the Marine Antifouling Coatings

Marine Drugs ◽

10.3390/md19010019 ◽

2021 ◽

Vol 19 (1) ◽

pp. 19

Author(s):

Lexin Long ◽

Ruojun Wang ◽

Ho Yin Chiang ◽

Wei Ding ◽

Yong-Xin Li ◽

...

Keyword(s):

Marine Environment ◽

Screening Program ◽

Control Strategies ◽

Larval Settlement ◽

Cost Effective ◽

Inhibitory Effect ◽

Economic Losses ◽

Antibiofilm Activity ◽

Microbial Composition ◽

Marine Biofilms

Biofilms are surface-attached multicellular communities that play critical roles in inducing biofouling and biocorrosion in the marine environment. Given the serious economic losses and problems caused by biofouling and biocorrosion, effective biofilm control strategies are highly sought after. In a screening program of antibiofilm compounds against marine biofilms, we discovered the potent biofilm inhibitory activity of elasnin. Elasnin effectively inhibited the biofilm formation of seven strains of bacteria isolated from marine biofilms. With high productivity, elasnin-based coatings were prepared in an easy and cost-effective way, which exhibited great performance in inhibiting the formation of multi-species biofilms and the attachment of large biofouling organisms in the marine environment. The 16S amplicon analysis and anti-larvae assay revealed that elasnin could prevent biofouling by the indirect impact of changed microbial composition of biofilms and direct inhibitory effect on larval settlement with low toxic effects. These findings indicated the potential application of elasnin in biofilm and biofouling control in the marine environment.

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