Bactoprenol also known as dolichol-11 and (isomerically vaguely) C55-isoprenyl alcohol (C55-OH) is a

lipid Lipids are a broad group of naturally-occurring molecules which includes fats, waxes, sterols, fat-soluble vitamins (such as vitamins A, D, E and K), monoglycerides, diglycerides, phospholipids, and others. The functions of lipids include ...

first identified in certain species of lactobacili. It is a

hydrophobic In chemistry, hydrophobicity is the physical property of a molecule that is seemingly repelled from a mass of water (known as a hydrophobe). In contrast, hydrophiles are attracted to water. Hydrophobic molecules tend to be nonpolar and, t ...

alcohol Alcohol most commonly refers to: * Alcohol (chemistry), an organic compound in which a hydroxyl group is bound to a carbon atom * Alcohol (drug), an intoxicant found in alcoholic drinks Alcohol may also refer to: Chemicals * Ethanol, one of sev ...

that plays a key role in the growth of cell walls (

peptidoglycan Peptidoglycan or murein is a unique large macromolecule, a polysaccharide, consisting of sugars and amino acids that forms a mesh-like peptidoglycan layer outside the plasma membrane, the rigid cell wall (murein sacculus) characteristic of most b ...

) in

Gram-positive bacteria In bacteriology, gram-positive bacteria are bacteria that give a positive result in the Gram stain test, which is traditionally used to quickly classify bacteria into two broad categories according to their type of cell wall. Gram-positive ba ...

. The double bonds all have the Z configuration except for the three ω-terminal ones, which are biosynthetically derived from (E,E)-

farnesyl diphosphate Farnesyl pyrophosphate (FPP), also known as farnesyl diphosphate (FDP), is an intermediate in the biosynthesis of terpenes and terpenoids such as sterols and carotenoids. It is also used in the synthesis of CoQ (part of the electron transport chai ...

Occurrence

Bactoprenol is a lipid synthesized from

mevalonic acid Mevalonic acid (MVA) is a key organic compound in biochemistry; the name is a contraction of dihydroxymethylvalerolactone. The carboxylate anion of mevalonic acid, which is the predominant form in biological environments, is known as ''mevalonate ...

and is the most abundant lipid found in certain species of

lactobacilli The ''Lactobacillaceae'' are a family of lactic acid bacteria. It is the only family in the lactic acid bacteria which includes homofermentative and heterofermentative organisms; in the ''Lactobacillaceae,'' the pathway used for hexose fermentati ...

. Bactoprenol is found in both mesosomal and plasma membranes. Mesosomal and plasma bactoprenol are synthesized independently from each other.

Function

Bactoprenol is thought to play a key role in the formation of cell walls in gram-positive bacteria by cycling peptidoglycan monomers through the plasma membrane and inserting these monomers at points of growth in the bacterial cell wall.

Antibiotic significance

Because bactoprenol is so important for cell growth, numerous

antibiotic An antibiotic is a type of antimicrobial substance active against bacteria. It is the most important type of antibacterial agent for fighting bacterial infections, and antibiotic medications are widely used in the treatment and prevention ...

compounds function by disrupting the bactoprenol-mediated transportation pathway. This strategy was first identified by studying the antibiotic mechanism of friulimicin B. Since then, other antibiotics that make use of a similar mechanism have been identified, including

nisin Nisin is a polycyclic antibacterial peptide produced by the bacterium '' Lactococcus lactis'' that is used as a food preservative. It has 34 amino acid residues, including the uncommon amino acids lanthionine (Lan), methyllanthionine (MeLan), di ...

and

lantibiotics Lantibiotics are a class of polycyclic peptide antibiotics that contain the characteristic thioether amino acids lanthionine or methyllanthionine, as well as the unsaturated amino acids dehydroalanine, and 2-aminoisobutyric acid. They belong to ...

such as NAI-107.

References

{{Reflist Fatty alcohols Terpenes and terpenoids