{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,4]],"date-time":"2025-11-04T23:16:35Z","timestamp":1762298195731},"reference-count":0,"publisher":"Walter de Gruyter GmbH","issue":"11-12","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2014,12,1]]},"abstract":"<jats:title>Abstract<\/jats:title>\n               <jats:p> The two genes lacZ1 and lacZ2 from Klebsiella pneumoniae 285, encoding \u03b2-galactosidase isoenzymes II and III (KpBGase-II and -III), were each cloned downstream of a T7 promoter for expression in Escherichia coli BL21(DE3), and the resulting recombinant enzymes were characterized in detail. The optimum temperature and pH value of KpBGase-II were 40 \u00b0C and 7.5, and those of KpBGase-III were 50 \u00b0C and 8.0, respectively. KpBGase-III was more stable than KpBGase-II at higher temperature (&gt;60\u00b0C). Both \u03b2-galactosidases were more active towards o-nitrophenyl-\u03b2- D-galactopyranoside as compared to lactose. The enzymatic synthesis of lactulose and 1-lactulose catalyzed by KpBGase-II and KpBGase-III was investigated. Using 400 g\/L lactose and 200 g\/L fructose as substrates, the resulting lactulose and 1-lactulose yields with KpBGase-II were 6.2 and 42.3 g\/L, while those with KpBGase-III were 5.1 and 23.8 g\/L, respectively. KpBGase-II has a potential for the production of 1-lactulose from lactose and fructose. Like other \u03b2-galactosidases, the two isozymes catalyze the transgalactosylation in the presence of fructose establishing the \u03b2-(1\u21921) linkage. <\/jats:p>","DOI":"10.5560\/znc.2014-0061","type":"journal-article","created":{"date-parts":[[2014,12,22]],"date-time":"2014-12-22T08:10:33Z","timestamp":1419235833000},"page":"479-487","source":"Crossref","is-referenced-by-count":4,"title":["Expression and Characterization of Two \u03b2-Galactosidases from Klebsiella pneumoniae 285 in Escherichia coli and their Application in the Enzymatic Synthesis of Lactulose and 1-Lactulose"],"prefix":"10.1515","volume":"69","author":[{"given":"He","family":"Wang","sequence":"first","affiliation":[{"name":"State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China"},{"name":"Tianmu College, Zhejiang Agriculture and Forestry University, Zhuji 311800, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ruijin","family":"Yang","sequence":"additional","affiliation":[{"name":"School of Food Science and Technology, Jiangnan University, Wuxi 214122, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xiaoyan","family":"Jiang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xiao","family":"Hua","sequence":"additional","affiliation":[{"name":"School of Food Science and Technology, Jiangnan University, Wuxi 214122, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Wei","family":"Zhao","sequence":"additional","affiliation":[{"name":"School of Food Science and Technology, Jiangnan University, Wuxi 214122, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Wenbin","family":"Zhang","sequence":"additional","affiliation":[{"name":"School of Food Science and Technology, Jiangnan University, Wuxi 214122, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xuan","family":"Chen","sequence":"additional","affiliation":[{"name":"School of Food Science and Technology, Jiangnan University, Wuxi 214122, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"374","published-online":{"date-parts":[[2015,3,19]]},"container-title":["Zeitschrift f\u00fcr Naturforschung C"],"original-title":[],"language":"en","link":[{"URL":"http:\/\/www.degruyter.com\/view\/j\/znc.2014.69.issue-11-12\/znc.2014-0061\/znc.2014-0061.xml","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/www.degruyter.com\/document\/doi\/10.5560\/znc.2014-0061\/xml","content-type":"application\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/www.degruyter.com\/document\/doi\/10.5560\/znc.2014-0061\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2021,6,22]],"date-time":"2021-06-22T16:31:07Z","timestamp":1624379467000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.degruyter.com\/document\/doi\/10.5560\/znc.2014-0061\/html"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2014,12,1]]},"references-count":0,"journal-issue":{"issue":"11-12","published-online":{"date-parts":[[2015,3,19]]},"published-print":{"date-parts":[[2014,12,1]]}},"alternative-id":["10.5560\/znc.2014-0061"],"URL":"https:\/\/doi.org\/10.5560\/znc.2014-0061","relation":{},"ISSN":["1865-7125","0939-5075"],"issn-type":[{"value":"1865-7125","type":"electronic"},{"value":"0939-5075","type":"print"}],"subject":[],"published":{"date-parts":[[2014,12,1]]}}}