Ectoine (3,4,5,6-tetrahydro-2-methyl-4-pyrimidinecarboxylic acid) is a natural compound found in several species of

bacteria Bacteria (; : bacterium) are ubiquitous, mostly free-living organisms often consisting of one Cell (biology), biological cell. They constitute a large domain (biology), domain of Prokaryote, prokaryotic microorganisms. Typically a few micr ...

. It is a compatible solute which serves as a protective substance by acting as an

osmolyte Osmolytes are low-molecular-weight organic compounds that influence the properties of biological fluids. Osmolytes are a class of organic molecules that play a significant role in regulating osmotic pressure and maintaining cellular homeostasis in ...

and thus helps organisms survive extreme

osmotic stress Osmotic shock or osmotic stress is physiologic dysfunction caused by a sudden change in the solute concentration around a cell, which causes a rapid change in the movement of water across its cell membrane. Under hypertonic conditions - conditi ...

. Furthermore it was shown to protect DNA against ionizing and ultraviolet radiation serving as a radical scavenger. Ectoine is found in high concentrations in

halophilic A halophile (from the Greek word for 'salt-loving') is an extremophile that thrives in high salt concentrations. In chemical terms, halophile refers to a Lewis acidic species that has some ability to extract halides from other chemical species. ...

microorganisms and confers resistance towards salt and temperature stress. Ectoine was first identified in the microorganism '' Ectothiorhodospira halochloris'', but has since been found in a wide range of

Gram-negative Gram-negative bacteria are bacteria that, unlike gram-positive bacteria, do not retain the crystal violet stain used in the Gram staining method of bacterial differentiation. Their defining characteristic is that their cell envelope consists ...

and

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. The Gram stain ...

. Other species of bacteria in which ectoine was found include: * '' Brevibacterium linens'' * '' Halomonas elongata'' * '' Marinococcus halophilus'' * '' Pseudomonas stutzeri'' * ''

Halomonas titanicae ''Halomonas titanicae'' is a gram-negative, halophilic species of bacteria which was isolated in 2010 from rusticles recovered from the wreck of the RMS ''Titanic''. It has been estimated by Henrietta Mann, one of the researchers that first iso ...

'' * '' Halorhodospira halophila'' * '' Halomonas ventosae''

Biosynthesis

Ectoine is synthesized in three successive enzymatic reactions starting from aspartic β-semialdehyde. The genes involved in the biosynthesis are called ''ectA'', ''ectB'' and ''ectC'', and they encode the enzymes L-2,4-diaminobutyric acid acetyltransferase, L-2,4-diaminobutyric acid transaminase and L-ectoine synthase, respectively.

Use in cosmetics

Ectoine is used as an active ingredient in

skin care Skin care or skincare is the practice of maintaining and improving the health and appearance of the skin. It includes washing, moisturizing, protecting from the sun, and treating skin problems like acne and dryness. Skin care can help prevent i ...

and sun protection products. It stabilizes

protein Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residue (biochemistry), residues. Proteins perform a vast array of functions within organisms, including Enzyme catalysis, catalysing metab ...

s and other cellular structures and protects the skin from stresses like UV irradiation and dryness.

Medical use

Due to its protein stabilizing properties, ectoine has been evaluated as a topical treatment for

hay fever Allergic rhinitis, of which the seasonal type is called hay fever, is a type of rhinitis, inflammation in the nose that occurs when the immune system overreacts to allergens in the air. It is classified as a Allergy, type I hypersensitivity re ...

. Effectiveness of a nasal spray containing ectoine is comparable to cromoglycate and is reported to be well tolerated by the patients. It is available

over the counter Over-the-counter (OTC) drugs are medicines sold directly to a consumer without a requirement for a prescription from a healthcare professional, as opposed to prescription drugs, which may be supplied only to consumers possessing a valid pres ...

in the European Union.

References

{{reflist Amidines Carboxylic acids