T-N Wang1, A H Kaksonen2, P-Y Hong1. 1. Division of Biological and Environmental Science and Engineering (BESE), Water Desalination and Reuse Center (WDRC), King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia. 2. CSIRO Land and Water, Floreat, WA, Australia.
Abstract
AIM: This study evaluated two methods, namely high performance liquid chromatography with fluorescence detection (HPLC-FLD) and Vibrio harveyi BB170 bioassay, for autoinducer-2 (AI-2) quantification in marine samples. Using both methods, the study also investigated the stability of AI-2 in varying pH, temperature and media, as well as quantified the amount of AI-2 signals in marine samples. METHODS AND RESULTS: HPLC-FLD method showed a higher level of reproducibility and precision compared to V. harveyi BB170 bioassay. Alkaline pH (>8) and high temperature (>37°C) increased the instability of AI-2. The AI-2 concentrations in seawater were low, c. 3·2-27·6 pmol l-1 , whereas 8-week-old marine biofilm grew on an 18·8 cm2 substratum accumulated c. 0·207 nmol of AI-2. CONCLUSION: Both methods have pros and cons for AI-2 quantification in marine samples. Regardless, both methods reported a ubiquitous presence of AI-2 in both planktonic and biomass fractions of seawater, as well as in marine biofilm. SIGNIFICANCE AND IMPACT OF THE STUDY: In this study, AI-2 signals were for the first time enumerated in marine samples to reveal the ubiquitous presence of AI-2 in this environment. The findings suggest a possible role of AI-2 in biofilm formation in marine environment, and the contribution of AI-2 in biofilm-associated problems such as biofouling and biocorrosion.
AIM: This study evaluated two methods, namely high performance liquid chromatography with fluorescence detection (HPLC-FLD) and Vibrio harveyi BB170 bioassay, for autoinducer-2 (AI-2) quantification in marine samples. Using both methods, the study also investigated the stability of AI-2 in varying pH, temperature and media, as well as quantified the amount of AI-2 signals in marine samples. METHODS AND RESULTS: HPLC-FLD method showed a higher level of reproducibility and precision compared to V. harveyi BB170 bioassay. Alkaline pH (>8) and high temperature (>37°C) increased the instability of AI-2. The AI-2 concentrations in seawater were low, c. 3·2-27·6 pmol l-1 , whereas 8-week-old marine biofilm grew on an 18·8 cm2 substratum accumulated c. 0·207 nmol of AI-2. CONCLUSION: Both methods have pros and cons for AI-2 quantification in marine samples. Regardless, both methods reported a ubiquitous presence of AI-2 in both planktonic and biomass fractions of seawater, as well as in marine biofilm. SIGNIFICANCE AND IMPACT OF THE STUDY: In this study, AI-2 signals were for the first time enumerated in marine samples to reveal the ubiquitous presence of AI-2 in this environment. The findings suggest a possible role of AI-2 in biofilm formation in marine environment, and the contribution of AI-2 in biofilm-associated problems such as biofouling and biocorrosion.
Authors: János Tamás Padra; Stefany Ojaimi Loibman; Kaisa Thorell; Henrik Sundh; Kristina Sundell; Sara K Lindén Journal: Int J Mol Sci Date: 2022-04-13 Impact factor: 6.208