Metabolism of the Reserve Polysaccharide of <i>Streptococcus mitis</i>

Walker, Gwen J.; Builder, Janet E.

doi:10.1111/j.1432-1033.1971.tb01356.x

Cited by 31 publications

(4 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The B. fibrisolvens branching enzyme exhibited activity towards a wide range of oa-1,4-glucans, as has been shown for other branching enzymes (7,54,60). With amylopectin as the substrate, the B. fibrisolvens branching enzyme transferred oligosaccharide chains 5 to 10 glucose units long, with 7 as the preferred unit size.…”

Section: Discussionmentioning

confidence: 78%

“…The glgB gene product catalyzes the synthesis of a-1,6-glucosidic linkages in glycogen. A number of reports have dealt with the properties and action of bacterial branching enzymes (7,12,24,54), and the enzyme from E. coli has been purified nearly to homogeneity (7). Branching enzyme activity has also been reported in a number of other bacteria (48,54,60), fungi (35), higher plants, and animals (42).…”

mentioning

confidence: 99%

See 1 more Smart Citation

Characterization of the Butyrivibrio fibrisolvens glgB gene, which encodes a glycogen-branching enzyme with starch-clearing activity

et al. 1991

View full text Add to dashboard Cite

(calculated Mr, 73,875) with 46 to 50% sequence homology with other branching enzymes. A limited region of 12 amino acids showed sequence similarity to amylases and glucanotransferases. The B. fibrisolvens branching enzyme was not able to hydrolyze starch but stimulated phosphorylase a-mediated incorporation of glucose into a-1,4-glucan polymer 13.4-fold. The branching enzyme was purified to homogeneity by a simple two-step procedure; N-terminal sequence and amino acid composition determinations confirmed the deduced translational start and amino acid sequence of the open reading frame. The enzymatic properties of the purified enzyme were investigated. The enzyme transferred chains of 5 to 10 (optimum, 7) glucose units, using amylose and amylopectin as substrates, to produce a highly branched polymer.

show abstract

Section: Discussionmentioning

confidence: 78%

mentioning

confidence: 99%

Characterization of the Butyrivibrio fibrisolvens glgB gene, which encodes a glycogen-branching enzyme with starch-clearing activity

et al. 1991

View full text Add to dashboard Cite

show abstract

“…Streptococcal pathogens contain genes required for efficient utilization of α-glucans including amylases and/or pullulanases which cleave α-1,4 and α-1,6 glycosidic bonds in starch or glycogen [14]–[18]. Previously, we have shown that a cell wall anchored amylopullulanase of S. suis serotype 2 ( apuA -SSU1849) was necessary to support bacterial proliferation on the α-glucan starch/pullulan (an α-1,6; α-1,4 linked glucose polymer) as a single carbon source and to promote adhesion of S. suis to porcine tracheal epithelial cells [19].…”

Section: Introductionmentioning

confidence: 99%

Carbohydrate Availability Regulates Virulence Gene Expression in Streptococcus suis

et al. 2014

View full text Add to dashboard Cite

Streptococcus suis is a major bacterial pathogen of young pigs causing worldwide economic problems for the pig industry. S. suis is also an emerging pathogen of humans. Colonization of porcine oropharynx by S. suis is considered to be a high risk factor for invasive disease. In the oropharyngeal cavity, where glucose is rapidly absorbed but dietary α-glucans persist, there is a profound effect of carbohydrate availability on the expression of virulence genes. Nineteen predicted or confirmed S. suis virulence genes that promote adhesion to and invasion of epithelial cells were expressed at higher levels when S. suis was supplied with the α-glucan starch/pullulan compared to glucose as the single carbon source. Additionally the production of suilysin, a toxin that damages epithelial cells, was increased more than ten-fold when glucose levels were low and S. suis was growing on pullulan. Based on biochemical, bioinformatics and in vitro and in vivo gene expression studies, we developed a biological model that postulates the effect of carbon catabolite repression on expression of virulence genes in the mucosa, organs and blood. This research increases our understanding of S. suis virulence mechanisms and has important implications for the design of future control strategies including the development of anti-infective strategies by modulating animal feed composition.

show abstract

“…Several enzymes involved in glycogen metabolism have been isolated from the soluble cell fractions of S. mitior (3,33,34). Only one phosphorylase was found among these (35).…”

mentioning

confidence: 99%

Metabolism of the reserve polysaccharide of Streptococcus mitior (mitis): is there a second alpha-1,4-glucan phosphorylase?

Pulkownik¹,

Walker²

1976

J Bacteriol

View full text Add to dashboard Cite

The alpha-1,4-glucan phosphorylase (alpha-1,4-glucan: orthophosphate glucosyltransferase; EC 2.4.1.1) associated with the particulate cell fraction of Streptococcus mitior strain S3 was compared with the soluble maltodextrin phosphorylase that had been previously isolated from the same organism (Walker et al., 1969). The particulate enzyme was more sensitive to the glycogen content of the cell than the soluble euzyme; its activity was highest when the cells were grown under conditions favoring high glycogen storage. Substrate specificities of the two high activity towards endogenous glycogen, whereas low-molecular-weight maltodextrins were the preferred substrates for the soluble phosphorylase. The purification of the particulate phosphorylase included incubation of the particulate fraction in 160 mM sodium phosphate-10 mM sodium citrate-0.1% (wt/vol) Triton X-100 buffer (pH 6.7) and ion-exchange chromatography on diethylamino-ethyl- Sephadex A-50. The purified enzyme was fully soluble. The value for the purification factor was variable and depended on (i) the substrate used and (ii) whether the synthetic or the degradative reaction was being measured. The solubilization resulted in considerable changes in the properties of the phosphorylase: the pH optimum for activity was raised from 6.0 to 7.0-7.5 and the substrate specificity was altered. Consequently, the purified enzyme bore greater similarity to the soluble maltodextrin phosphorylase. The reported results are best explained in terms of a single phosphorylase, the specificity which is determind by its binding state in the cell. The enzyme acts as a glycogen phosphorylase in the particulate state and as a maltodextrin phosphorylase when soluble. The equilibrium between the two forms is related to the glycogen content of the cells.

show abstract

Metabolism of the Reserve Polysaccharide of Streptococcus mitis

Cited by 31 publications

References 22 publications

Characterization of the Butyrivibrio fibrisolvens glgB gene, which encodes a glycogen-branching enzyme with starch-clearing activity

Characterization of the Butyrivibrio fibrisolvens glgB gene, which encodes a glycogen-branching enzyme with starch-clearing activity

Carbohydrate Availability Regulates Virulence Gene Expression in Streptococcus suis

Metabolism of the reserve polysaccharide of Streptococcus mitior (mitis): is there a second alpha-1,4-glucan phosphorylase?

Contact Info

Product

Resources

About