title: Characterization of alpha,alpha-trehalase released in the intestinal lumen by the probiotic Saccharomyces boulardii.
abstract: OBJECTIVE
  Trehalose intolerance due to alpha,alpha-trehalase deficiency has scarcely been studied. The purpose of this study was to measure alpha,alpha-trehalase activity in intestinal biopsy samples from 200 consecutive patients over a period of 6 months, and to characterize alpha,alpha-trehalase released by the probiotic Saccharomyces boulardii (S. boulardii).
  
  
  METHODS
  Enzyme activities were measured in human and rat intestinal mucosal samples using the micromethod of Messer & Dalqvist. alpha,alpha-trehalase from S. boulardii was immunoprecipitated and Western blotted using an IgG purified antibody raised against a 23 amino acid peptide of alpha,alpha-trehalase of S. cerevisiae.
  
  
  RESULTS
  Among 200 patients, most of whom complained of abdominal symptoms and diarrhoea, 18 (9%) had total alpha,alpha-trehalase deficiency (0-12 U/g mucosa) and 39 had partial deficiency (3-12 U/g mucosa). Only 4 patients (2%) presented selective alpha,alpha-trehalase deficiency with otherwise normal disaccharidases. Expressed per gram of powder, alpha,alpha-trehalase from S. boulardii delivered in vitro an activity 175 times higher than that of human trehalase per gram of intestinal mucosa. V(max) (22+/-0.43 micromol) and K(m) (5 mM) were close to that of the human enzyme, whereas Western blot revealed a signal of two subunits of 82 kDa. Finally, treatment of rats with S. boulardii resulted in increases in alpha,alpha-trehalase activities of 25 to 45% (p<0.01) in endoluminal fluid and intestinal mucosa compared with in controls.
  
  
  CONCLUSIONS
  Our data suggest that alpha,alpha-trehalase deficiency is more common than is believed and that oral administration of S. boulardii could be beneficial in patients with digestive symptoms caused by trehalose intolerance.
authors.affiliation: Faculty of Medicine, Universite Catholique de Louvain, Laboratory of Paediatric Gastroenterology and Nutrition, Brussels, Belgium. buts@gype.ucl.ac.be
authors.forename: Jean-Paul
authors.initials: JP
authors.lastname: Buts
authors.forename: Catherine
authors.initials: C
authors.lastname: Stilmant
authors.forename: Paul
authors.initials: P
authors.lastname: Bernasconi
authors.forename: Christiane
authors.initials: C
authors.lastname: Neirinck
authors.forename: Nadine
authors.initials: N
authors.lastname: De Keyser
mesh_terms: D000328:Adult; D000818:Animals; D005260:Female; D006801:Humans; D007413:Intestinal Mucosa / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D019936:Probiotics / Q000378:metabolism*; D051381:Rats; D012440:Saccharomyces / Q000201:enzymology*; D014198:Trehalase / Q000378:metabolism*
chemical_list: D014198:Trehalase