Hopanoid

From Biology-Online Dictionary | Biology-Online Dictionary

Hopanoid

(Science: cell biology) hopanoid is a chemical component in the cytoplasmic membranes of many bacteria.

hopanoid is a pentacyclic saturated derivative of mevalonic acid (mevalonic acid is a key intermediate in cholesterol biosynthesis) and is assumed to be functioning in a similar way to sterols, which serve to stabilise the structure of eukaryotic membranes.

while sterols can make up 5-25 percent of the total lipids of eukaryotic membranes, they are absent from most of the prokaryotic membranes.