“They are investigating areas that are largely unexplored,” he said. Sol GrunerI research molecular biophysics at Cornell University. He consulted on the study but was not a co-author.
Plasmalogen lipids are also found in the human brain, and their role in deep-sea membranes may help explain aspects of cell signaling. More immediately, this research reveals new ways in which life has adapted to the most extreme conditions of the deep ocean.
crazy in the membrane
The cells of all living things on Earth are surrounded by fatty molecules known as lipids. When you put lipids in a test tube and add water, they are automatically sorted sequentially. The oily, water-hating tails of the lipids mix together to form the inner layer, and the water-loving heads are arranged together to form the outer layer. Part of a thin membrane. “It’s like the oil and water separating in a dish,” Winnikoff said. “It’s universal in geology and it’s what makes it work.”
For cells, the outer lipid membrane provides structure, like the outer wall of a house, and acts as a physical barrier to maintain the cell interior. However, the barrier should not be too strong. It’s studded with protein, so you need protein. It shakes up space to perform various cellular tasks, such as transporting molecules across membranes. Sometimes cell membranes are compressed, releasing chemicals into the environment and then fusing again.
Therefore, for a membrane to be healthy and functional, it must be strong, flexible and dynamic at the same time. “The membrane is balanced on the edge of stability,” Winnikoff said. “Despite having this well-defined structure, all the individual molecules that make up the sheets on both sides are always flowing around each other. “It’s actually a liquid crystal display.”
One of the novel properties of this structure is that the center of the membrane is very sensitive to temperature and pressure. It is much more sensitive than other biological molecules such as proteins, DNA or RNA. For example, if you cool a lipid membrane, the molecules will move more slowly, and “they will eventually lock together,” just like when you put olive oil in the refrigerator, Winnikoff said. “Biologically, that’s generally a bad thing.” Metabolic processes are disrupted. The membrane may crack and the contents may leak.
To avoid this, many cold-adapted animals have membranes composed of a mix of lipid molecules with slightly different structures to maintain liquid crystal flow even at low temperatures. Because high pressure also slows membrane flow, many biologists have assumed that deep-sea membranes are made the same way.
