Preliminary investigation on the potential involvement of an ABC-like gene in Halomicronema metazoicum (Cyanobacteria) tolerance to low seawater pH in an ocean acidification scenario

• Published in: Marine Pollution Bulletin
• Main Authors: Romano, P., Simonetti, S., Gambi, M.C., Luckenbach, Till, Zupo, V., Corsi, I.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Elsevier 2024
• Subjects: Halomicronema metazoicum; Cyanobacteria; Acid stress tolerance; ATP-binding cassette (ABC) membrane; transporter proteins; Ocean acidification (OA) scenarios; Low pH; Ocean acidification
• Online Access: https://www.ufz.de/index.php?en=20939&ufzPublicationIdentifier=29204; https://doi.org/10.1016/j.marpolbul.2024.116584

Decreasing ocean surface pH, called ocean acidification (OA), is among the major risks for marine ecosystems due to human-driven atmospheric pCO2 increase. Understanding the molecular mechanisms of adaptation enabling marine species to tolerate a lowered seawater pH could support predictions of consequences of future OA scenarios for marine life. This study examined whether the ATP-binding cassette (ABC)-like gene slr2019 confers tolerance to the marine cyanobacterium Halomicronema metazoicum to low seawater pH conditions (7.7, 7.2, 6.5) in short- and long-term exposures (7 and 30 d). Photosynthetic pigment content indicated that the species can tolerate all three lowered-pH conditions. At day 7, slr2019 was up-regulated at pH7.7 while no changes were observed at lower pH. After 30-d exposure, a significant decrease in slr2019 transcript levels was observed in all low-pH treatments. These first results indicate an effect of low pH on the examined transporter expression in H. metazoicum.