25 November 2020
Searching for genes that could help turn off biofouling
Published online 8 September 2020
Gene targeting could help prevent the formation of phytoplankton films on underwater manmade surfaces.
A research team led by biologists at New York University Abu Dhabi has uncovered molecular processes involved in surface colonisation by diatoms, a large group of phytoplankton that form films on surfaces in marine environments. ‘Biofouling’ on ships, pipes, bridge supports and other manmade underwater structures is a major problem that can lead to major damage as well as increased fuel consumption and maintenance costs.
During the process of surface colonisation, some species of diatoms are known to change from a fusiform shape, with tapered ends, to an oval shape. The study focused on examining the underlying processes involved in this shift in morphology. By comparing culture samples of fusiform and oval cells, the team identified genes of interest, or up-regulated genes, implicated in surface colonisation.
Further analysis revealed 61 signalling genes, including so-called G-protein-coupled receptors (GPCRs), which are turned on during surface colonisation in the diatom species Phaeodactylum tricornutum. Altering the expression of individual GPCR genes demonstrated the possibility of manipulating the biofouling activities of P. tricornutum cells. For example, the researchers showed that GPCR1A expression can induce biofouling and confer more resistance to UV light exposure.
The study opens the door to targeting genes that can reverse the natural surface colonisation process of diatoms. This could pave the way to non-chemical-based anti-fouling strategies.
“The newly identified gene targets could be manipulated and may serve as a switch to unlock the potential of non-biofouling diatoms via gene regulation,” says lead author of the study, Weiqi Fu, although he cautions that genetically modified organisms should not be released into the environment without an assessment of their ecological consequences. “In that sense, biologically-produced molecules, such as small molecules from engineered diatoms, may be utilized to prevent biofouling through inhibiting microbes and other diatoms from forming biofilms in marine environments.”
The team plans to continue investigating micro-biofouling at the community level, which will involve studying diatoms, bacteria and other significant algae involved in surface colonisation. “As biofouling is a complicated issue that affects marine life, we need to put more emphasis on applied research to establish an environmentally friendly and fully scalable approach to combat it,” says Fu.
Fu, W. et al. GPCR genes as activators of surface colonization pathways in a model marine diatom. iScience 23, 101424 (2020).