{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,4]],"date-time":"2025-10-04T01:27:45Z","timestamp":1759541265985},"reference-count":0,"publisher":"Portland Press Ltd.","issue":"2","content-domain":{"domain":["portlandpress.com"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[1971,1,1]]},"abstract":"<jats:p>1. An acid \u03b2-galactosidase, optimum pH4.0\u20134.5, in the human small-intestinal mucosa was separated and characterized. 2. Autolysis of mucosal homogenates at acid pH inactivated the lactase and hetero \u03b2-galactosidase; the total activity of the acid \u03b2-galactosidase was only slightly depleted, but a greater proportion of the enzyme was solubilized by this treatment. 3. Separation on a Sephadex G-200 column revealed that the acid \u03b2-galactosidase could occur in at least three different forms, probably representing monomer, dimer and octamer or polymer of the enzyme. 4. The properties of the different forms of the acid \u03b2-galactosidase were studied with regard to pH optimum, Km, rate of hydrolysis of different substrates, and sensitivity to p-chloromercuribenzoate and tris as inhibitors. All these properties were the same for the different forms of the enzyme. 5. The acid \u03b2-galactosidase hydrolyses lactose as well as hetero \u03b2-galactosides and contributes to the lactase activity of intestinal biopsies also when measured at pH 6. This enzyme may therefore be responsible for a considerable part of the residual lactase activity found in lactose-intolerant patients.<\/jats:p>","DOI":"10.1042\/bj1210299","type":"journal-article","created":{"date-parts":[[2015,8,10]],"date-time":"2015-08-10T19:32:13Z","timestamp":1439235133000},"page":"299-308","update-policy":"http:\/\/dx.doi.org\/10.1042\/crossmark_policy","source":"Crossref","is-referenced-by-count":30,"title":["Human small-intestinal \u03b2-galactosidases. Separation and characterization of three forms of an acid \u03b2-galactosidase"],"prefix":"10.1042","volume":"121","author":[{"given":"Nils-Georg","family":"Asp","sequence":"first","affiliation":[{"name":"Research Department 1, E-blocket, and Department of Physiological Chemistry, University Hospital, Fack, S-220 05 Lund 5, Sweden"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"288","container-title":["Biochemical Journal"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/portlandpress.com\/biochemj\/article-pdf\/121\/2\/299\/769919\/bj1210299.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/portlandpress.com\/biochemj\/article-pdf\/121\/2\/299\/769919\/bj1210299.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2021,11,26]],"date-time":"2021-11-26T19:07:55Z","timestamp":1637953675000},"score":1,"resource":{"primary":{"URL":"https:\/\/portlandpress.com\/biochemj\/article\/121\/2\/299\/17149\/Human-small-intestinal-galactosidases-Separation"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1971,1,1]]},"references-count":0,"journal-issue":{"issue":"2","published-print":{"date-parts":[[1971,1,1]]}},"URL":"https:\/\/doi.org\/10.1042\/bj1210299","relation":{},"ISSN":["0306-3283"],"issn-type":[{"value":"0306-3283","type":"print"}],"subject":[],"published":{"date-parts":[[1971,1,1]]}}}