hopanoids
Hopanoids are a class of pentacyclic triterpenoid lipids produced by many bacteria. They are structurally analogous to sterols in eukaryotes and contribute to the stability and function of bacterial membranes. The core hopane skeleton is a C30 five-ring framework; simple hopanoids such as diploptene serve as base structures from which a variety of side chains are derived to form bacteriohopanepolyols (BHPs).
Biosynthesis and genetics: Hopanoid production begins from standard isoprenoid precursors and proceeds through the cyclization of
Biological role: In membranes, hopanoids help modulate fluidity and permeability, stabilizing membranes under heat, osmotic stress,
Ecology and significance: Hopanoids are widespread across bacterial phyla, notably Proteobacteria and cyanobacteria. They persist in