Cysteine
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Cysteine is a naturally occurring hydrophobic amino acid which has a sulfhydryl group and is found in most proteins, however only in small quantities. See the chemical structure of cysteine immediately to the right. When it is exposed to air it oxidizes to form cystine, which is two cysteine molecules joined by a disulfide bond. See the chemical structure of cystine below and to the right. One molecule of water (H2O) is the byproduct from the creation of each molecule of cystine. It can be taken as a supplement in the form of N-acetylcysteine (NAC).
- Symbol: C or Cys
- Side chain type: -CH2-SH; hydrophobic
- Mass: 121.16
- Isoelectric point: 5.05
Sheep
Cystine.PNG
Cysteine is required by sheep in order to produce wool, however it is an essential amino-acid that cannot be synthesised by the sheep and must be taken in as food from grass. This means that during drought conditions sheep stop producing wool, however transgenic sheep have been developed which can make their own cysteine.
See also
External links
- http://www.chemie.fu-berlin.de/chemistry/bio/aminoacid/cystein_en.html
- On the hydrophobic nature of cysteine. (http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6T36-3XB0N6H-H&_coverDate=09%2F10%2F1999&_alid=241945989&_rdoc=1&_fmt=&_orig=search&_qd=1&_cdi=4938&_sort=d&view=c&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=3cb10a335716303532fc517906a12b3a)ca:Cisteïna
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