What is Amylase?
'''Amylase''' is an [[enzyme]] which breaks down [[starch]] into [[sugars]] which the body can use. More accurately, it is a family of similar enzymes which work in a wide range of animals, plants and [[fungi]]. There are two variants in humans: alpha-amylase, and gamma-amylase.<ref>[http://pdb101.rcsb.org/motm/74 PDB-101: Molecule of the month]</ref> Alpha-amylase is a major [[digestion|digestive]] enzyme. Its optimum [[pH]] is 6.7–7.0. It is found in [[saliva]] and [[pancreas|pancreatic juice]]. It takes starch chains and breaks them into smaller pieces with two or three glucose units. It can break down [[starch]] into [[maltose]]. It works in the mouth and [[stomach]] during digestion. The gamma-amylase has most acidic optimum pH of all amylases because it is most active around pH 3. Therefore, it works best in the [[stomach]], which does have an acidic pH.<ref>{{cite web|url=http://www.worthington-biochem.com/introbiochem/effectspH.html|title=Effects of pH (Introduction to Enzymes)|work=worthington-biochem.com|accessdate=17 May 2015}}</ref> ==Human evolution== Apparently, early humans did not possess salivary amylase. The closest evolutionary relatives of humans, [[chimpanzees]] and [[bonobo]]s, have either one or no copies of the gene for producing salivary amylase.<ref>{{cite journal |last=Vuorisalo, Timo & Arjamaa, Olli 2010. |title=Gene-culture coevolution and human diet |journal=American Scientist |volume=98 |issue=2 |page=140 |url=http://www.americanscientist.org/issues/feature/2010/2/gene-culture-coevolution-and-human-diet |access-date=2016-05-14 |archive-date=2016-03-04 |archive-url=https://web.archive.org/web/20160304110626/http://www.americanscientist.org/issues/feature/2010/2/gene-culture-coevolution-and-human-diet |url-status=dead }}</ref> A duplication event of the [[AMY1A|AMY1]] gene led to the production of amylase in the saliva. The same event occurred independently in [[rodents]]. This shows the importance of salivary amylase in organisms that eat relatively large amounts of starch.<ref