Characterization of intestinal gamma-glucoamylase deficiency in CBA/Ca mice

• Published in: The American journal of physiology Vol. 265; no. 6; pp. G1150 - G1157
• Main Authors: Quezada-Calvillo, R, Senchyna, M, Underdown, B.J
• Format: Journal Article
• Language: English
• Published: United States 01-12-1993
• Subjects: alpha-Glucosidases - metabolism; Animals; Chromatography, High Pressure Liquid; Disaccharidases - biosynthesis; Disaccharidases - metabolism; Electrophoresis, Polyacrylamide Gel; ENFERMEDADES CARENCIALES; Enzyme Induction; Glucan 1,4-alpha-Glucosidase - deficiency; Glucan 1,4-alpha-Glucosidase - metabolism; Ileum - enzymology; INTESTIN; Intestinal Mucosa - enzymology; INTESTINOS; Jejunum - enzymology; MALADIE DE CARENCE; Mice; Mice, Inbred CBA - metabolism; OLIGOSACARIDOS; OLIGOSACCHARIDE; RATON; SOURIS; Species Specificity
• ISSN: 0002-9513; 2163-5773
• DOI: 10.1152/ajpgi.1993.265.6.G1150

In previous work, we found that CBA/Ca mice display only 20% of the maltase activity present in other mouse strains. In this study, we characterized more fully the maltase deficiency in CBA/Ca mice. Virtually all of the intestinal maltase activity of CBA/Ca mice was inactivated at 50 degrees C, indicating that it was due only to the sucrase-isomaltase complex. High-performance liquid chromatographic analysis revealed that CBA/Ca mice had undetectable maltase activity displaying the molecular mass characteristic of murine gamma-glucoamylase (gamma-GA) (530 kDa). Gel electrophoretic analysis confirmed that CBA/Ca mice lacked maltase activity with molecular mass of 530 kDa corresponding to gamma-GA. Two-dimensional electrophoretic analysis revealed that the gamma-GA deficiency in CBA/Ca mice was due to the failure to synthesize the enzyme and not to the synthesis of an inactive protein. Gamma-GA maltase activity could not be induced in CBA/Ca mice by a diet rich in starch, whereas the activity of other disaccharidases were readily increased. Gamma-GA-deficient CBA/Ca mice appear to lack any gross metabolic abnormality resulting from this defect