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Jeanluc Parrou - One of the best experts on this subject based on the ideXlab platform.
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Similarities and differences in the biochemical and enzymological properties of the four isomaltases from Saccharomyces cerevisiae
FEBS Open Bio, 2014Co-Authors: Xu Deng, Marieange Teste, Jean Marie Francois, Marjorie Petitjean, Wafa Kooli, Samuel Tranier, Jeanluc ParrouAbstract:The yeast Saccharomyces cerevisiae IMA multigene family encodes four isomaltases sharing high sequence identity from 65% to 99%. Here, we explore their functional diversity, with exhaustive in‐vitro characterization of their enzymological and biochemical properties. The four isoenzymes exhibited a preference for the α‐(1,6) disaccharides Isomaltose and palatinose, with Michaëlis–Menten kinetics and inhibition at high substrates concentration. They were also able to hydrolyze trisaccharides bearing an α‐(1,6) linkage, but also α‐(1,2), α‐(1,3) and α‐(1,5) disaccharides including sucrose, highlighting their substrate ambiguity. While Ima1p and Ima2p presented almost identical characteristics, our results nevertheless showed many singularities within this protein family. In particular, Ima3p presented lower activities and thermostability than Ima2p despite only three different amino acids between the sequences of these two isoforms. The Ima3p_R279Q variant recovered activity levels of Ima2p, while the Leu‐to‐Pro substitution at position 240 significantly increased the stability of Ima3p and supported the role of prolines in thermostability. The most distant protein, Ima5p, presented the lowest optimal temperature and was also extremely sensitive to temperature. Isomaltose hydrolysis by Ima5p challenged previous conclusions about the requirement of specific amino acids for determining the specificity for α‐(1,6) substrates. We finally found a mixed inhibition by maltose for Ima5p while, contrary to a previous work, Ima1p inhibition by maltose was competitive at very low Isomaltose concentrations and uncompetitive as the substrate concentration increased. Altogether, this work illustrates that a gene family encoding proteins with strong sequence similarities can lead to enzyme with notable differences in biochemical and enzymological properties.
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characterization of a new multigene family encoding isomaltases in the yeast saccharomyces cerevisiae the ima family
Journal of Biological Chemistry, 2010Co-Authors: Marieange Teste, Jean Marie Francois, Jeanluc ParrouAbstract:It has been known for a long time that the yeast Saccharomyces cerevisiae can assimilate α-methylglucopyranoside and Isomaltose. We here report the identification of 5 genes (YGR287c, YIL172c, YJL216c, YJL221c and YOL157c), which, similar to the SUCx, MALx, or HXTx multigene families, are located in the subtelomeric regions of different chromosomes. They share high nucleotide sequence identities between themselves (66–100%) and with the MALx2 genes (63–74%). Comparison of their amino acid sequences underlined a substitution of threonine by valine in region II, one of the four highly conserved regions of the α-glucosidase family. This change was previously shown to be sufficient to discriminate α-1,4- to α-1,6-glucosidase activity in YGR287c (Yamamoto, K., Nakayama, A., Yamamoto, Y., and Tabata, S. (2004) Eur. J. Biochem. 271, 3414–3420). We showed that each of these five genes encodes a protein with α-glucosidase activity on Isomaltose, and we therefore renamed these genes IMA1 to IMA5 for IsoMAltase. Our results also illustrated that sequence polymorphisms among this family led to interesting variability of gene expression patterns and of catalytic efficiencies on different substrates, which altogether should account for the absence of functional redundancy for growth on Isomaltose. Indeed, deletion studies revealed that IMA1/YGR287c encodes the major isomaltase and that growth on Isomaltose required the presence of AGT1, which encodes an α-glucoside transporter. Expressions of IMA1 and IMA5/YJL216c were strongly induced by maltose, Isomaltose, and α-methylglucopyranoside, in accordance with their regulation by the Malx3p-transcription system. The physiological relevance of this IMAx multigene family in S. cerevisiae is discussed.
Marieange Teste - One of the best experts on this subject based on the ideXlab platform.
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Similarities and differences in the biochemical and enzymological properties of the four isomaltases from Saccharomyces cerevisiae
FEBS Open Bio, 2014Co-Authors: Xu Deng, Marieange Teste, Jean Marie Francois, Marjorie Petitjean, Wafa Kooli, Samuel Tranier, Jeanluc ParrouAbstract:The yeast Saccharomyces cerevisiae IMA multigene family encodes four isomaltases sharing high sequence identity from 65% to 99%. Here, we explore their functional diversity, with exhaustive in‐vitro characterization of their enzymological and biochemical properties. The four isoenzymes exhibited a preference for the α‐(1,6) disaccharides Isomaltose and palatinose, with Michaëlis–Menten kinetics and inhibition at high substrates concentration. They were also able to hydrolyze trisaccharides bearing an α‐(1,6) linkage, but also α‐(1,2), α‐(1,3) and α‐(1,5) disaccharides including sucrose, highlighting their substrate ambiguity. While Ima1p and Ima2p presented almost identical characteristics, our results nevertheless showed many singularities within this protein family. In particular, Ima3p presented lower activities and thermostability than Ima2p despite only three different amino acids between the sequences of these two isoforms. The Ima3p_R279Q variant recovered activity levels of Ima2p, while the Leu‐to‐Pro substitution at position 240 significantly increased the stability of Ima3p and supported the role of prolines in thermostability. The most distant protein, Ima5p, presented the lowest optimal temperature and was also extremely sensitive to temperature. Isomaltose hydrolysis by Ima5p challenged previous conclusions about the requirement of specific amino acids for determining the specificity for α‐(1,6) substrates. We finally found a mixed inhibition by maltose for Ima5p while, contrary to a previous work, Ima1p inhibition by maltose was competitive at very low Isomaltose concentrations and uncompetitive as the substrate concentration increased. Altogether, this work illustrates that a gene family encoding proteins with strong sequence similarities can lead to enzyme with notable differences in biochemical and enzymological properties.
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characterization of a new multigene family encoding isomaltases in the yeast saccharomyces cerevisiae the ima family
Journal of Biological Chemistry, 2010Co-Authors: Marieange Teste, Jean Marie Francois, Jeanluc ParrouAbstract:It has been known for a long time that the yeast Saccharomyces cerevisiae can assimilate α-methylglucopyranoside and Isomaltose. We here report the identification of 5 genes (YGR287c, YIL172c, YJL216c, YJL221c and YOL157c), which, similar to the SUCx, MALx, or HXTx multigene families, are located in the subtelomeric regions of different chromosomes. They share high nucleotide sequence identities between themselves (66–100%) and with the MALx2 genes (63–74%). Comparison of their amino acid sequences underlined a substitution of threonine by valine in region II, one of the four highly conserved regions of the α-glucosidase family. This change was previously shown to be sufficient to discriminate α-1,4- to α-1,6-glucosidase activity in YGR287c (Yamamoto, K., Nakayama, A., Yamamoto, Y., and Tabata, S. (2004) Eur. J. Biochem. 271, 3414–3420). We showed that each of these five genes encodes a protein with α-glucosidase activity on Isomaltose, and we therefore renamed these genes IMA1 to IMA5 for IsoMAltase. Our results also illustrated that sequence polymorphisms among this family led to interesting variability of gene expression patterns and of catalytic efficiencies on different substrates, which altogether should account for the absence of functional redundancy for growth on Isomaltose. Indeed, deletion studies revealed that IMA1/YGR287c encodes the major isomaltase and that growth on Isomaltose required the presence of AGT1, which encodes an α-glucoside transporter. Expressions of IMA1 and IMA5/YJL216c were strongly induced by maltose, Isomaltose, and α-methylglucopyranoside, in accordance with their regulation by the Malx3p-transcription system. The physiological relevance of this IMAx multigene family in S. cerevisiae is discussed.
Jean Marie Francois - One of the best experts on this subject based on the ideXlab platform.
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Similarities and differences in the biochemical and enzymological properties of the four isomaltases from Saccharomyces cerevisiae
FEBS Open Bio, 2014Co-Authors: Xu Deng, Marieange Teste, Jean Marie Francois, Marjorie Petitjean, Wafa Kooli, Samuel Tranier, Jeanluc ParrouAbstract:The yeast Saccharomyces cerevisiae IMA multigene family encodes four isomaltases sharing high sequence identity from 65% to 99%. Here, we explore their functional diversity, with exhaustive in‐vitro characterization of their enzymological and biochemical properties. The four isoenzymes exhibited a preference for the α‐(1,6) disaccharides Isomaltose and palatinose, with Michaëlis–Menten kinetics and inhibition at high substrates concentration. They were also able to hydrolyze trisaccharides bearing an α‐(1,6) linkage, but also α‐(1,2), α‐(1,3) and α‐(1,5) disaccharides including sucrose, highlighting their substrate ambiguity. While Ima1p and Ima2p presented almost identical characteristics, our results nevertheless showed many singularities within this protein family. In particular, Ima3p presented lower activities and thermostability than Ima2p despite only three different amino acids between the sequences of these two isoforms. The Ima3p_R279Q variant recovered activity levels of Ima2p, while the Leu‐to‐Pro substitution at position 240 significantly increased the stability of Ima3p and supported the role of prolines in thermostability. The most distant protein, Ima5p, presented the lowest optimal temperature and was also extremely sensitive to temperature. Isomaltose hydrolysis by Ima5p challenged previous conclusions about the requirement of specific amino acids for determining the specificity for α‐(1,6) substrates. We finally found a mixed inhibition by maltose for Ima5p while, contrary to a previous work, Ima1p inhibition by maltose was competitive at very low Isomaltose concentrations and uncompetitive as the substrate concentration increased. Altogether, this work illustrates that a gene family encoding proteins with strong sequence similarities can lead to enzyme with notable differences in biochemical and enzymological properties.
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characterization of a new multigene family encoding isomaltases in the yeast saccharomyces cerevisiae the ima family
Journal of Biological Chemistry, 2010Co-Authors: Marieange Teste, Jean Marie Francois, Jeanluc ParrouAbstract:It has been known for a long time that the yeast Saccharomyces cerevisiae can assimilate α-methylglucopyranoside and Isomaltose. We here report the identification of 5 genes (YGR287c, YIL172c, YJL216c, YJL221c and YOL157c), which, similar to the SUCx, MALx, or HXTx multigene families, are located in the subtelomeric regions of different chromosomes. They share high nucleotide sequence identities between themselves (66–100%) and with the MALx2 genes (63–74%). Comparison of their amino acid sequences underlined a substitution of threonine by valine in region II, one of the four highly conserved regions of the α-glucosidase family. This change was previously shown to be sufficient to discriminate α-1,4- to α-1,6-glucosidase activity in YGR287c (Yamamoto, K., Nakayama, A., Yamamoto, Y., and Tabata, S. (2004) Eur. J. Biochem. 271, 3414–3420). We showed that each of these five genes encodes a protein with α-glucosidase activity on Isomaltose, and we therefore renamed these genes IMA1 to IMA5 for IsoMAltase. Our results also illustrated that sequence polymorphisms among this family led to interesting variability of gene expression patterns and of catalytic efficiencies on different substrates, which altogether should account for the absence of functional redundancy for growth on Isomaltose. Indeed, deletion studies revealed that IMA1/YGR287c encodes the major isomaltase and that growth on Isomaltose required the presence of AGT1, which encodes an α-glucoside transporter. Expressions of IMA1 and IMA5/YJL216c were strongly induced by maltose, Isomaltose, and α-methylglucopyranoside, in accordance with their regulation by the Malx3p-transcription system. The physiological relevance of this IMAx multigene family in S. cerevisiae is discussed.
Buford L Nichols - One of the best experts on this subject based on the ideXlab platform.
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metabolic impacts of maltase deficiencies
Journal of Pediatric Gastroenterology and Nutrition, 2018Co-Authors: Buford L Nichols, Susan S Baker, Roberto QuezadacalvilloAbstract:: The mucosal maltase enzymes are characterized by an activity that produces glucose from linear glucose polymers, assayed with the disaccharide maltose. The related enzyme isomaltase produces glucose from branched glucose polymers, assayed with palatinose. Maltase and isomaltase activities are part of the 4 disaccharidases assayed from clinical duodenal biopsy homogenates. The reported maltase activities are more difficult to interpret than lactase or sucrase activities because both the sucrase-isomaltase and maltase-glucoamylase proteins have overlapping maltase activities. The early work of Dahlqvist identified 4 maltase activities from human small intestinal mucosa. On one peptide, sucrase (maltase Ib) and isomaltase (maltase Ia) activities shared maltase activities but identified the enzymes as sucrase-isomaltase. On the other peptide, no distinguishing characteristics of the 2 maltase activities (maltases II and III) were detected and the activities identified as maltase-glucoamylase. The nutritional/clinical importance of small intestinal maltase and isomaltase activities are due to their crucial role in the digestion of food starches to absorbable free glucose. This review focuses on the interpretation of biopsy maltase activities in the context of reported lactase, sucrase, maltase, and palatinase biopsy assay activity patterns. We present a classification of mucosal maltase deficiencies and novel primary maltase deficiency (Ib, II, III) and provide a clarification of the role of maltase activity assayed from clinically obtained duodenal biopsies, as a path toward future clinical and molecular genomic investigations.
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13c labeled starch breath test in congenital sucrase isomaltase deficiency
Journal of Pediatric Gastroenterology and Nutrition, 2018Co-Authors: Claudia C Robayotorres, Susan S Baker, Bruce R Hamaker, Antone R. Opekun, Marisela Diazsotomayor, Bruno P Chumpitazi, Buford L NicholsAbstract:ABSTRACTBackground and Hypotheses:Human starch digestion is a multienzyme process involving 6 different enzymes: salivary and pancreatic α-amylase; sucrase and isomaltase (from sucrose-isomaltase [SI]), and maltase and glucoamylase (from maltase-glucoamylase [MGAM]). Together these enzymes cleave st
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different sucrose isomaltase response of caco 2 cells to glucose and maltose suggests dietary maltose sensing
Journal of Clinical Biochemistry and Nutrition, 2014Co-Authors: Minwen Cheng, Roberto Quezadacalvillo, Buford L Nichols, Mohammad Chegeni, Keehong Kim, Genyi Zhang, Mustapha Benmoussa, Bruce R HamakerAbstract:Using the small intestine enterocyte Caco-2 cell model, sucrase-isomaltase (SI, the mucosal α-glucosidase complex) expression and modification were examined relative to exposure to different mono- and disaccharide glycemic carbohydrates. Caco-2/TC7 cells were grown on porous supports to post-confluence for complete differentiation, and dietary carbohydrate molecules of glucose, sucrose (disaccharide of glucose and fructose), maltose (disaccharide of two glucoses α-1,4 linked), and Isomaltose (disaccharide of two glucoses α-1,6 linked) were used to treat the cells. qRT-PCR results showed that all the carbohydrate molecules induced the expression of the SI gene, though maltose (and Isomaltose) showed an incremental increase in mRNA levels over time that glucose did not. Western blot analysis of the SI protein revealed that only maltose treatment induced a higher molecular weight band (Mw ~245 kDa), also at higher expression level, suggesting post-translational processing of SI, and more importantly a sensing of maltose. Further work is warranted regarding this putative sensing response as a potential control point for starch digestion and glucose generation in the small intestine.
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Hydrolysis properties of enzyme-modified maltodextrins (1%, w/v) using the four mucosal α-glucosidases (500 U).
2013Co-Authors: Byung-hoo Lee, Buford L Nichols, Like Yan, Robert J. Phillips, Bradley L. Reuhs, Kyra Jones, David R. Rose, Roberto Quezada-calvillo, Sang-ho Yoo, Bruce R HamakerAbstract:As the amount of α-1,6 linkages were increased, the released glucose amounts decreased by the individual mucosal α-glucosidase reactions. WCS, waxy corn starch; BE-WCS, branching enzyme-treated WCS; and BEBA-WCS, β-amylase-treated BE-WCS. ctMGAM, C-terminal maltase-glucoamylase; ntMGAM, N-terminal maltase-glucoamylase; ctSI, C-terminal sucrase-isomaltase; and ntSI, N-terminal sucrase-isomaltase.
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13c breath tests for sucrose digestion in congenital sucrase isomaltase deficient and sacrosidase supplemented patients
Journal of Pediatric Gastroenterology and Nutrition, 2009Co-Authors: Claudia C Robayotorres, Susan S Baker, Roberto Quezadacalvillo, Antone R. Opekun, Xavier Villa, E O Smith, Marilyn Navarrete, Buford L NicholsAbstract:ABSTRACTBackground:Congenital sucrase-isomaltase deficiency (CSID) is characterized by absence or deficiency of the mucosal sucrase-isomaltase enzyme. Specific diagnosis requires upper gastrointestinal biopsy with evidence of low to absent sucrase enzyme activity and normal histology. The hydrogen b
Matthew A Lines - One of the best experts on this subject based on the ideXlab platform.
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mg 107 congenital sucrase isomaltase deficiency identification of the common inuit founder mutation
Journal of Medical Genetics, 2015Co-Authors: Julien L Marcadier, Margaret Boland, Ronald C Scott, Kheirie Issa, Adam D Mcintyre, Robert A Hegele, Michael T Geraghty, Matthew A LinesAbstract:Objective Congenital sucrase-isomaltase deficiency (CSID) is a rare hereditary cause of chronic diarrhoea in children. Persons with CSID lack the intestinal brush-border enzyme required for digestion of di- and oligosaccharides, including sucrose and Isomaltose. Malabsorption results in abdominal pain, distention, copious diarrhoea, and failure to thrive. If recognised, dietary avoidance of the offending carbohydrates is highly effective. Although CSID is known to be highly prevalent (˜5–10%) in several Inuit populations, the genetic basis for this condition has not been described. Methods We sequenced the sucrase-isomaltase gene, SI, in a single Inuit CSID proband with severe fermentative diarrhoea and failure to thrive. We then genotyped a further 128 anonymized Inuit control individuals from a variety of circumpolar locales to assess for a possible founder effect. Results We identified a novel, homozygous frameshift mutation, c.273_274delAG (p. Gly92Leufs*8) in exon 4 of SI in the proband, that is predicted to result in complete absence of functional protein product. This change is indeed very common among Inuit control specimens, with an observed allele frequency of 0.17 (95% confidence interval 0.13–0.22). The predicted Hardy-Weinberg prevalence of CSID in the Inuit, based on this single founder allele is ˜3% (95% confidence interval 1.6–5.0%), comparable with previous estimates. Interpretation Targeted mutation testing for the c.273_274delAG allele should afford a simple and minimally invasive means of diagnosing CSID in persons of Inuit descent. Because CSID is a readily treatable disorder, such testing should be considered at an early stage in the assessment of Inuit patients with chronic diarrhoea.
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congenital sucrase isomaltase deficiency identification of a common inuit founder mutation
Canadian Medical Association Journal, 2015Co-Authors: Julien L Marcadier, Margaret Boland, Ronald C Scott, Kheirie Issa, Adam D Mcintyre, Robert A Hegele, Michael T Geraghty, Matthew A LinesAbstract:Background Congenital sucrase-isomaltase deficiency is a rare hereditary cause of chronic diarrhea in children. People with this condition lack the intestinal brush-border enzyme required for digestion of di- and oligosaccharides, including sucrose and Isomaltose, leading to malabsorption. Although the condition is known to be highly prevalent (about 5%-10%) in several Inuit populations, the genetic basis for this has not been described. We sought to identify a common mutation for congenital sucrase-isomaltase deficiency in the Inuit population. Methods We sequenced the sucrase-isomaltase gene, SI, in a single Inuit proband with congenital sucrase-isomaltase deficiency who had severe fermentative diarrhea and failure to thrive. We then genotyped a further 128 anonymized Inuit controls from a variety of locales in the Canadian Arctic to assess for a possible founder effect. Results In the proband, we identified a novel, homozygous frameshift mutation, c.273_274delAG (p.Gly92Leufs*8), predicted to result in complete absence of a functional protein product. This change was very common among the Inuit controls, with an observed allele frequency of 17.2% (95% confidence interval [CI] 12.6%-21.8%). The predicted Hardy-Weinberg prevalence of congenital sucrase-isomaltase deficiency in Inuit people, based on this single founder allele, is 3.0% (95% CI 1.4%-4.5%), which is comparable with previous estimates. Interpretation We found a common mutation, SI c.273_274delAG, to be responsible for the high prevalence of congenital sucrase-isomaltase deficiency among Inuit people. Targeted mutation testing for this allele should afford a simple and minimally invasive means of diagnosing this condition in Inuit patients with chronic diarrhea.
