Cloning and expression of Streptococcus salivarius urease gene in Escherichia coli

VernacularTitle:唾液链球菌尿素酶基因的克隆和表达
Author: Yan WANG ¹ ; Xi-Ping FENG ; You-Hua XIE ; Dan-Ying TAO ; Xiao-Ling LUAN
Author Information

1. 上海交通大学医学院附属第九人民医院(口腔医学院)
Keywords: Streptococcus,oralis; Urease; Nickel; Dental caries
From: Chinese Journal of Stomatology 2010;45(8):498-501
CountryChina
Language:Chinese
Abstract: Objective To clone Streptococcus salivarius(Ss) 57. I urease gene, which can express ureolytic activity in Escherichia coli (Ec) without adding extra nickel ions. Methods Urease gene was cloned by polymerase chain reaction in three separate parts. The three separate plasmids were digested by specific restriction enzymes and ligated together. The expression of the complete urease gene in Ec was detected by phenol red assay and pH analysis. Results Urease gene of Ss 57. I was eventually cloned and proved correct. Urease activity of the obtained clone was positive in Ec. Without adding extra NiCl2, the recombinant Ec could hydrolyze urea to produce ammonia, resulting in the increase of pH value.Conclusions The clone of Ss urease gene obtained in this study could express ureolytic activity in Ec without adding extra nickel ions. The current clone can be used to construct ureolytic effector strain used in replacement therapy in caries prevention.