Biomaterial Database

Effect of magnesium ions on secretion of glucosyltransferase from Streptococcus sobrinus. 1989

Y Yamashita, and T Takehara

Department of Preventive Dentistry, Kyushu Dental College, Kitakyushu, Japan.

Magnesium ions, which are known to inhibit the leader peptidase (signal peptidase) activity of Escherichia coli, stimulated the activities of glucosyltransferases (GTFs) in culture medium of Streptococcus sobrinus at concentrations of 1 or 5 mM. At a concentration of 50 mM, the activity of water-soluble glucan synthase was not affected and that of water-insoluble glucan synthase was slightly suppressed. The activities of both GTFs in the crude enzyme extract were totally unaffected by addition of magnesium ions. These findings indicate that magnesium ions have some effects on secretion of the GTFs from S. sobrinus, but that the mechanism of transportation of the enzymes across the plasma membrane in S. sobrinus differs completely from that of proteins secreted into the periplasmic space or assembled in the outer membrane in E. coli.

UI	MeSH Term	Description	Entries
D008274	Magnesium	A metallic element that has the atomic symbol Mg, atomic number 12, and atomic weight 24.31. It is important for the activity of many enzymes, especially those involved in OXIDATIVE PHOSPHORYLATION.
D003470	Culture Media	Any liquid or solid preparation made specifically for the growth, storage, or transport of microorganisms or other types of cells. The variety of media that exist allow for the culturing of specific microorganisms and cell types, such as differential media, selective media, test media, and defined media. Solid media consist of liquid media that have been solidified with an agent such as AGAR or GELATIN.	Media, Culture
D003731	Dental Caries	Localized destruction of the tooth surface initiated by decalcification of the enamel followed by enzymatic lysis of organic structures and leading to cavity formation. If left unchecked, the cavity may penetrate the enamel and dentin and reach the pulp.	Caries, Dental,Carious Lesions,Dental Cavities,Dental Cavity,Dental Decay,Dental White Spots,Carious Dentin,Decay, Dental,Dental White Spot,White Spot, Dental,White Spots, Dental,Carious Dentins,Carious Lesion,Cavities, Dental,Cavity, Dental,Dentin, Carious,Dentins, Carious,Lesion, Carious,Lesions, Carious,Spot, Dental White,Spots, Dental White
D005964	Glucosyltransferases	Enzymes that catalyze the transfer of glucose from a nucleoside diphosphate glucose to an acceptor molecule which is frequently another carbohydrate. EC 2.4.1.-.	Glucosyltransferase
D013291	Streptococcus	A genus of gram-positive, coccoid bacteria whose organisms occur in pairs or chains. No endospores are produced. Many species exist as commensals or parasites on man or animals with some being highly pathogenic. A few species are saprophytes and occur in the natural environment.