scholarly journals Analytical Study of the Conversion of Water-Soluble Glucan into Water-Insoluble Glucan by 1, 3-α-D-Glucan Synthase from Streptococcus mutans (Serotype g)

1986 ◽  
Vol 40 (2) ◽  
pp. 431-435
Author(s):  
Miyuki Itoh ◽  
Nobuhiro Hanada ◽  
Tadamichi Takehara ◽  
Eiichi Saeki
Keyword(s):  
Streptococcus Mutans ◽  
Analytical Study ◽  
Water Soluble ◽  
Glucan Synthase ◽  
Insoluble Glucan

Interaction of Streptococcus mutans Glucosyltransferases with Teichoic Acids

1980 ◽  
Vol 29 (2) ◽  
pp. 376-382
Author(s):  
H. K. Kuramitsu ◽  
L. Wondrack ◽  
M. McGuinness
Keyword(s):  
Molecular Weight ◽  
High Molecular Weight ◽  
Streptococcus Mutans ◽  
Teichoic Acid ◽  
Lipoteichoic Acid ◽  
Water Soluble ◽  
Heat Inactivation ◽  
Teichoic Acids ◽  
Insoluble Glucan

The Streptococcus mutans GS5 glucosyltransferase activities (both water-soluble and -insoluble glucan-synthesizing fractions) were inhibited by purified lipoteichoic acid. In vitro sucrose-dependent colonization of smooth surfaces by strain GS5 was also markedly reduced in the presence of the amphipathic molecules. The inhibition of soluble glucan synthesis by lipoteichoic acid appeared to be competitive with respect to both sucrose and primer dextran T10. These inhibitory effects were dependent on the presence of the fatty acid components of lipoteichoic acid since deacylated lipoteichoic acids did not inhibit glucosyltransferase activity. However, the deacylated molecules did interact with the enzymes since deacylated lipoteichoic acid partially protected the enzyme activity against heat inactivation and also induced the formation of high-molecular-weight enzyme complexes from the soluble glucan-synthesizing fraction. The presence of teichoic acid in high-molecular-weight aggregates of glucosyltransferase isolated from the culture fluids of strain GS5 was suggested by the detection of polyglycerophosphate in these fractions. In addition to strain GS5, two other organisms containing polyglycerophosphate teichoic acids, Lactobacillus casei and Lactobacillus fermentum , were demonstrated to bind glucosyltransferase activity. These results are discussed relative to the potential role of teichoic acid-glucosyltransferase interactions in enzyme binding to the cell surface of S. mutans and the formation of high-molecular-weight enzyme aggregates in the culture fluids of the organism.

scholarly journals Streptococcus mutans Dextransucrase: Functioning of Primer Dextran and Endogenous Dextranase in Water-Soluble and Water-Insoluble Glucan Synthesis

1977 ◽  
Vol 16 (2) ◽  
pp. 637-648 ◽  
Author(s):  
Greg R. Germaine ◽  
Susan K. Harlander ◽  
Woon-Lam S. Leung ◽  
Charles F. Schachtele
Keyword(s):  
Streptococcus Mutans ◽  
Water Soluble ◽  
Insoluble Glucan ◽  
Glucan Synthesis

scholarly journals Functional Analyses of a Conserved Region in Glucosyltransferases of Streptococcus mutans

1998 ◽  
Vol 66 (10) ◽  
pp. 4797-4803 ◽  
Author(s):  
Jean-San Chia ◽  
Czau-Siung Yang ◽  
Jen-Yang Chen
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Enzymatic Activity ◽  
Streptococcus Mutans ◽  
Water Soluble ◽  
Single Amino Acid ◽  
Single Mutation ◽  
Insoluble Glucan ◽  
Conserved Region ◽  
Glucan Synthesis

ABSTRACT Streptococcus mutans glucosyltransferases (GTFs; GtfB, -C, and -D) synthesize water-soluble and -insoluble glucan polymers from sucrose. We have identified previously a conserved region of 19 amino acids (aa) (Gtf-P1; aa 409 to 427 of GtfB and aa 435 to 453 of GtfC) which is functionally important for both enzymatic activity and bacterial adherence. Monoclonal antibodies directed against Gtf-P1 selectively inhibited insoluble glucan synthesis by GtfB and -C but had no effect on soluble glucan synthesis by GtfD, suggesting that despite an apparent near identity of sequence, corresponding residues may function differently in these enzymes. To test this hypothesis, we used different strategies of mutagenesis to analyze amino acid residues of GtfB and GtfC in Gtf-P1. In-frame insertion of 6 amino acids preceding, or deletion of 14 amino acids within, this conserved region abolished the enzymatic activities of both GtfB and GtfC. Substitution of several residues in combination by random mutagenesis resulted in GtfB, but not GtfC, enzymes exhibiting decreased glucan synthesis and reduced rates of sucrose hydrolysis. Amino acid substitutions of Asp residues in GtfB or GtfC were found to be more critical for enzymatic activity than at other positions of this region. Interestingly, single mutation at Asp411 or Asp413 of GtfB resulted in enzymes retaining about 20% of wild-type activity, whereas mutagenesis of the corresponding Asp at position 437 or 439 in GtfC resulted in complete loss of enzymatic activity. Furthermore, single amino acid substitution of a Val residue between the two Asp residues enhanced the sucrase- and glucan-synthesizing activities of GtfB and GtfC. These results confirmed the report from another laboratory that Asp residues in the Gtf-P1 region are essential for enzymatic catalysis and provide new evidence that identical residues may function differently in closely related Gtf enzymes.

Ultrastructure of Extracellular Polysaccharides Produced by Serotype c Streptococcus mutans

1987 ◽  
Vol 66 (8) ◽  
pp. 1364-1369 ◽  
Author(s):  
Y. Toda ◽  
I. Moro ◽  
T. Koga ◽  
H. Asakawa ◽  
S. Hamada
Keyword(s):  
Electron Microscopy ◽  
Streptococcus Mutans ◽  
Water Soluble ◽  
Extracellular Polysaccharides ◽  
Structural Components ◽  
Amorphous Substance ◽  
Transmission Electron ◽  
Insoluble Glucan ◽  
Globular Body ◽  
Induced Mutant

The ultrastructure of extracellular polysaccharides produced in colonies by two clinical isolates and that of a nitrosoguanidine-induced mutant of serotype c Streptococcus mutans with different polysaccharide-synthesizing abilities were compared electron-microscopically. A large amount of polysaccharide was produced from sucrose by colonies of typical serotype c strain MT8148R and a clinical variant MT6801R with an enhanced fructan-synthesizing ability. Transmission electron-microscopy (TEM) revealed that the polysaccharides consisted of three structural components, i.e., globular, single-stranded filamentous, and double-stranded fibrillar structures. These structures were ascribed to production of fructan, water-soluble glucan, and water-insoluble glucan, respectively. On the other hand, two kinds of structures, a globular body and an amorphous substance, were observed by scanning electron-microscopy (SEM). The former was composed of fructan, while the latter contained a mixture of water-soluble and water-insoluble glucans which formed filamentous and double-stranded fibrillar structures under TEM. Very small quantities of polysaccharides were formed in colonies of mutant NG7183, which was derived from S. mutans MT6801R. This strain was found to possess low glucan- and no fructan-synthesizing abilities. The polysaccharides produced in colonies of mutant NG7183 were composed only of filamentous and double-stranded fibrils under TEM. A small amount of amorphous substance was observed by SEM in colonies of NG7183.

Microscopic and Phytochemical analysis of Desmodium velutinum (Willd) DC and Desmodium gangeticum (L.) DC. Panchanga powder

2021 ◽  
pp. 2950-2956
Author(s):  
Jigyasa Pathak ◽  
Aswathi M. P. ◽  
B. R. Patel ◽  
Harisha C. R. ◽  
Shukla Vinay J.
Keyword(s):  
Chemical Analysis ◽  
Analytical Study ◽  
Water Soluble ◽  
Wild Edible Plants ◽  
Phytochemical Analysis ◽  
Edible Plants ◽  
Therapeutic Purpose ◽  
Whole Plant ◽  
Physico Chemical ◽  
Collection Practices

Background: Desmodium velutinum (Fabaceae) is one of the wild edible plants used traditionally to treat diarrhoea, haematuria, infertility and also externally used to treat scorpion bites. Though various parts of the plant have been used for therapeutic purpose, panchanga of the plant has not been studied for its Pharmacognostical and phytochemical characteristics in detail, following scientific parameters. Hence in the present study Desmodium velutinum whole plant has been studied for its pharmacognostical and phytochemical characters and compared with commonly used species Desmodium gangeticum. Methods: Whole plant of Desmodim velutinum was collected from Paikmal, Odisha and Desmodium gangeticum was collected from Junagarh, Gujarat in the month of November 2019 following good collection practices and shade dried. Pharmacognostical study and analytical study were performed following standard pharmacopoeial procedures. Results: Whole plant (Panchanga) of former is sweetish and latter is bitter. Powder microscopy of Desmodium gangeticum showed presence of rhomboidal crystals and lignified annular and spiral vessels. Desmodium velutinum showed presence of prismatic crystals and lignified pitted vessels. Physico-chemical analysis showed higher loss on drying in Desmodium gangeticum, and higher water soluble extractive values of Desmodium velutinum. Phytochemical estimation showed the presence of Proteins, tannins, and carbohydrates in both samples. HPTLC study showed similar Rf value 0.82 and 0.94 at 254 and 0.03 and 0.41 at 366nm. Conclusion: Basing upon the analytical and microscopic similarities Desmodium velutinum may be considered as substitute of Desmodium gangeticum

scholarly journals Phyto Pharmacognostic Study of Lagerstroemia speciosa - An Analytical Study

2020 ◽  
Vol 5 (05) ◽  
pp. 206-213
Author(s):  
Jyothi S. Murthy ◽  
B. R. Lalitha ◽  
Aahalya Sharma
Keyword(s):  
Analytical Study ◽  
Microscopical Study ◽  
Water Soluble ◽  
Lower Epidermis ◽  
Calcium Oxalate Crystals ◽  
Phytochemical Study ◽  
Lagerstroemia Speciosa ◽  
Anomocytic Stomata ◽  
Leaf Powder ◽  
Sugar Levels

Lagerstroemia speciosa (L.) Pers (Hindi - Jarul, Taglog - Banaba) a member of Lythraceae family is found all over India, specially in Bengal, Assam and Deccan Peninsula. The leaves of L. speciosa is widely used for lowering blood sugar levels in Philippines, Japan and Taiwan. Pharmacognostical investigation of leaves of L. speciosa was done by evaluating its morphological, microscopical studies, Physicochemical and phytochemical parameters. Rasa Nirdharana was done. Microscopical study revealed presence of epidermal cells contained clusters of rosette aggregate calcium oxalate crystals and few cells were mucilaginous. Lower epidermis showed the presence of anomocytic stomata. Physical constants of leaf powder showed, loss on drying - 3.8%, total ash - 6.7%, acid insoluble ash - 1.039%, water soluble extractive value - 8.88%, alcohol soluble extractive value - 4.49% and pH - 5.75. Preliminary phytochemical study revealed the presence of alkaloids, flavonoids, saponins, triterpenes, tannins, proteins and iron. Rasa Nirdharana confirmed the leaves are Kashaya in Rasa. The Pharmacognostical study was useful for authentication of leaves of Lagerstoemia speciosa.

scholarly journals Cationic Lipid Content in Liposome-Encapsulated Nisin Improves Sustainable Bactericidal Activity against Streptococcus mutans

2016 ◽  
Vol 10 (1) ◽  
pp. 360-366 ◽  
Author(s):  
Kazuo Yamakami ◽  
Hideaki Tsumori ◽  
Yoshitaka Shimizu ◽  
Yutaka Sakurai ◽  
Kohei Nagatoshi ◽  
...  
Keyword(s):  
Dental Caries ◽  
Streptococcus Mutans ◽  
Cationic Lipid ◽  
Cationic Liposome ◽  
Bactericidal Effect ◽  
Insoluble Glucan ◽  
Inhibitory Efficiency ◽  
Bactericidal Activities ◽  
Glucan Synthesis ◽  
Sustained Inhibition

An oral infectious disease, dental caries, is caused by the cariogenic streptococci Streptococcus mutans. The expected preventive efficiency for prophylactics against dental caries is not yet completely observed. Nisin, a bacteriocin, has been demonstrated to be microbicidal against S. mutans, and liposome-encapsulated nisin improves preventive features that may be exploited for human oral health. Here we examined the bactericidal effect of charged lipids on nisin-loaded liposomes against S. mutans and inhibitory efficiency for insoluble glucan synthesis by the streptococci for prevention of dental caries. Cationic liposome, nisin-loaded dipalmitoylphosphatidylcholine/phytosphingosine, exhibited higher bactericidal activities than those of electroneutral liposome and anionic liposome. Bactericidal efficiency of the cationic liposome revealed that the vesicles exhibited sustained inhibition of glucan synthesis and the lowest rate of release of nisin from the vesicles. The optimizing ability of cationic liposome-encapsulated nisin that exploit the sustained preventive features of an anti-streptococcal strategy may improve prevention of dental caries.

Effects of Fluoride, Lithium and Strontium on Extracellular Polysaccharide Production by Streptococcus mutans and Actinomyces viscosus

1981 ◽  
Vol 60 (C) ◽  
pp. 1601-1610 ◽  
Author(s):  
Patrick Treasure
Keyword(s):  
Trace Elements ◽  
Streptococcus Mutans ◽  
Extracellular Polysaccharide ◽  
Water Soluble ◽  
Extracellular Polysaccharides ◽  
Polysaccharide Production

Effects of trace elements on production of extracellular polysaccharides (EPS) by S. mutans and A. viscosus were examined in vitro. Fluoride enhanced EPS production. Lithium and strontium had little effect alone, but tended to reverse the effect of fluoride. The proportion of water-soluble EPS and the proportion of glucosyl-EPS were increased by fluoride.

Sign in / Sign up

Export Citation Format

Share Document