Ectoine is a natural compound found in several species of bacteria. It is a compatible solute which serves as a protective substance by acting as an osmolyte

Osmolyte

Osmolytes are compounds affecting osmosis. They are soluble in the solution within a cell, or in the surrounding fluid, e.g. as plasma osmolytes. They play a role in maintaining cell volume and fluid balance. For example, when a cell swells due to external osmotic pressure, membrane channels open...

 and thus helps organisms survive extreme osmotic stress. Ectoine is found in high concentrations in halophilic

Halophile

Halophiles are extremophile organisms that thrive in environments with very high concentrations of salt. The name comes from the Greek for "salt-loving". While the term is perhaps most often applied to some halophiles classified into the Archaea domain, there are also bacterial halophiles and some...

 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 and gram-positive bacteria. Some other species ectoine was found in:

• Marinococcus halophilus
• Pseudomonas stutzeri
  Pseudomonas stutzeri
  Pseudomonas stutzeri is a Gram-negative, rod-shaped, motile, single polar-flagellated, soil bacterium first isolated from human spinal fluid.. It is a denitrifying bacterium, and strain KC of P. stutzeri may be used for bioremediation as it is able to degrade carbon tetrachloride. It is also an...
  
  
• Halomonas elongata

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

Ectoine is used as an active ingredient in skin care and sun protection

Sunscreen

Sunblock is a lotion, spray, gel or other topical product that absorbs or reflects some of the sun's ultraviolet radiation on the skin exposed to sunlight and thus helps protect against sunburn...

 products. It stabilizes protein

Protein

Proteins are biochemical compounds consisting of one or more polypeptides typically folded into a globular or fibrous form, facilitating a biological function. A polypeptide is a single linear polymer chain of amino acids bonded together by peptide bonds between the carboxyl and amino groups of...

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