Hurler syndrome: A patient with abnormally high levels of α-l-iduronidase protein

D. A. Brooks, G. S. Harper, G. J. Gibson, L. J. Ashton, J. A. Taylor, P. A G McCouri, C. Freeman, P. R. Clements, J. W. Hoffmann, J. J. Hopwood

Research output: Contribution to journalArticle

15 Citations (Scopus)

Abstract

Mucopolysaccharidosis type I (MPS I: McKusick 25280) is a clinically heterogenous lysosomal storage disorder which is caused by a variable deficiency in α-l-iduronidase activity (α-l-iduronide iduronohydrolase, EC 3.2.1.76). Cultured fibroblasts from an MPS I patient (cell line 2827) with a severe clinical phenotype (Hurler syndrome) have been characterized using immunochemical and biochemical techniques. Using a specific immunoquantification assay, we have demonstrated that cell line 2827 had an α-l-iduronidase protein content (189 ng/mg of extracted cell protein) at least six times greater than the mean level found in normal control fibroblasts (30 ng/mg of extracted cell protein). This was the only MPS I cell line, from a group of 23 MPS I patients, that contained greater than 7% of the mean level of α-l-iduronidase protein detected in normal controls. Cell line 2827 had very low α-l-iduronidase activity toward the fluorogenic substrate 4-methylumbelliferyl-α-l-iduronide, and a radiolabeled disaccharide substrate derived from heparin. Maturation studies of α-l-iduronidase in cell line 2827 showed apparently normal levels of α-l-iduronidase synthesis with delayed processing to the mature form. Subcellular fractionation experiments demonstrated α-l-iduronidase protein in lysosomal-enriched fractions isolated from cell line 2827, suggesting a normal cell distribution and supporting the proposed delayed processing. It is proposed that the MPS I patient described has an α-l-iduronidase gene mutation which affects both the active site and post-translational processing of the enzyme. This mutation must be structurally conservative because it does not result in instability either during maturation or in the lysosome.

LanguageEnglish
Pages211-220
Number of pages10
JournalBiochemical Medicine and Metabolic Biology
Volume47
Issue number3
DOIs
Publication statusPublished - 1 Jan 1992
Externally publishedYes

ASJC Scopus subject areas

  • Endocrinology, Diabetes and Metabolism
  • Biochemistry

Cite this

Brooks, D. A., Harper, G. S., Gibson, G. J., Ashton, L. J., Taylor, J. A., McCouri, P. A. G., ... Hopwood, J. J. (1992). Hurler syndrome: A patient with abnormally high levels of α-l-iduronidase protein. Biochemical Medicine and Metabolic Biology, 47(3), 211-220. https://doi.org/10.1016/0885-4505(92)90028-W
Brooks, D. A. ; Harper, G. S. ; Gibson, G. J. ; Ashton, L. J. ; Taylor, J. A. ; McCouri, P. A G ; Freeman, C. ; Clements, P. R. ; Hoffmann, J. W. ; Hopwood, J. J. / Hurler syndrome : A patient with abnormally high levels of α-l-iduronidase protein. In: Biochemical Medicine and Metabolic Biology. 1992 ; Vol. 47, No. 3. pp. 211-220.
@article{044a1d058d4a4e8680461a136393e9bc,
title = "Hurler syndrome: A patient with abnormally high levels of α-l-iduronidase protein",
abstract = "Mucopolysaccharidosis type I (MPS I: McKusick 25280) is a clinically heterogenous lysosomal storage disorder which is caused by a variable deficiency in α-l-iduronidase activity (α-l-iduronide iduronohydrolase, EC 3.2.1.76). Cultured fibroblasts from an MPS I patient (cell line 2827) with a severe clinical phenotype (Hurler syndrome) have been characterized using immunochemical and biochemical techniques. Using a specific immunoquantification assay, we have demonstrated that cell line 2827 had an α-l-iduronidase protein content (189 ng/mg of extracted cell protein) at least six times greater than the mean level found in normal control fibroblasts (30 ng/mg of extracted cell protein). This was the only MPS I cell line, from a group of 23 MPS I patients, that contained greater than 7{\%} of the mean level of α-l-iduronidase protein detected in normal controls. Cell line 2827 had very low α-l-iduronidase activity toward the fluorogenic substrate 4-methylumbelliferyl-α-l-iduronide, and a radiolabeled disaccharide substrate derived from heparin. Maturation studies of α-l-iduronidase in cell line 2827 showed apparently normal levels of α-l-iduronidase synthesis with delayed processing to the mature form. Subcellular fractionation experiments demonstrated α-l-iduronidase protein in lysosomal-enriched fractions isolated from cell line 2827, suggesting a normal cell distribution and supporting the proposed delayed processing. It is proposed that the MPS I patient described has an α-l-iduronidase gene mutation which affects both the active site and post-translational processing of the enzyme. This mutation must be structurally conservative because it does not result in instability either during maturation or in the lysosome.",
author = "Brooks, {D. A.} and Harper, {G. S.} and Gibson, {G. J.} and Ashton, {L. J.} and Taylor, {J. A.} and McCouri, {P. A G} and C. Freeman and Clements, {P. R.} and Hoffmann, {J. W.} and Hopwood, {J. J.}",
year = "1992",
month = "1",
day = "1",
doi = "10.1016/0885-4505(92)90028-W",
language = "English",
volume = "47",
pages = "211--220",
journal = "Biochemical Medicine and Metabolic Biology",
issn = "0885-4505",
publisher = "Academic Press Inc.",
number = "3",

}

Brooks, DA, Harper, GS, Gibson, GJ, Ashton, LJ, Taylor, JA, McCouri, PAG, Freeman, C, Clements, PR, Hoffmann, JW & Hopwood, JJ 1992, 'Hurler syndrome: A patient with abnormally high levels of α-l-iduronidase protein', Biochemical Medicine and Metabolic Biology, vol. 47, no. 3, pp. 211-220. https://doi.org/10.1016/0885-4505(92)90028-W

Hurler syndrome : A patient with abnormally high levels of α-l-iduronidase protein. / Brooks, D. A.; Harper, G. S.; Gibson, G. J.; Ashton, L. J.; Taylor, J. A.; McCouri, P. A G; Freeman, C.; Clements, P. R.; Hoffmann, J. W.; Hopwood, J. J.

In: Biochemical Medicine and Metabolic Biology, Vol. 47, No. 3, 01.01.1992, p. 211-220.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Hurler syndrome

T2 - Biochemical Medicine and Metabolic Biology

AU - Brooks, D. A.

AU - Harper, G. S.

AU - Gibson, G. J.

AU - Ashton, L. J.

AU - Taylor, J. A.

AU - McCouri, P. A G

AU - Freeman, C.

AU - Clements, P. R.

AU - Hoffmann, J. W.

AU - Hopwood, J. J.

PY - 1992/1/1

Y1 - 1992/1/1

N2 - Mucopolysaccharidosis type I (MPS I: McKusick 25280) is a clinically heterogenous lysosomal storage disorder which is caused by a variable deficiency in α-l-iduronidase activity (α-l-iduronide iduronohydrolase, EC 3.2.1.76). Cultured fibroblasts from an MPS I patient (cell line 2827) with a severe clinical phenotype (Hurler syndrome) have been characterized using immunochemical and biochemical techniques. Using a specific immunoquantification assay, we have demonstrated that cell line 2827 had an α-l-iduronidase protein content (189 ng/mg of extracted cell protein) at least six times greater than the mean level found in normal control fibroblasts (30 ng/mg of extracted cell protein). This was the only MPS I cell line, from a group of 23 MPS I patients, that contained greater than 7% of the mean level of α-l-iduronidase protein detected in normal controls. Cell line 2827 had very low α-l-iduronidase activity toward the fluorogenic substrate 4-methylumbelliferyl-α-l-iduronide, and a radiolabeled disaccharide substrate derived from heparin. Maturation studies of α-l-iduronidase in cell line 2827 showed apparently normal levels of α-l-iduronidase synthesis with delayed processing to the mature form. Subcellular fractionation experiments demonstrated α-l-iduronidase protein in lysosomal-enriched fractions isolated from cell line 2827, suggesting a normal cell distribution and supporting the proposed delayed processing. It is proposed that the MPS I patient described has an α-l-iduronidase gene mutation which affects both the active site and post-translational processing of the enzyme. This mutation must be structurally conservative because it does not result in instability either during maturation or in the lysosome.

AB - Mucopolysaccharidosis type I (MPS I: McKusick 25280) is a clinically heterogenous lysosomal storage disorder which is caused by a variable deficiency in α-l-iduronidase activity (α-l-iduronide iduronohydrolase, EC 3.2.1.76). Cultured fibroblasts from an MPS I patient (cell line 2827) with a severe clinical phenotype (Hurler syndrome) have been characterized using immunochemical and biochemical techniques. Using a specific immunoquantification assay, we have demonstrated that cell line 2827 had an α-l-iduronidase protein content (189 ng/mg of extracted cell protein) at least six times greater than the mean level found in normal control fibroblasts (30 ng/mg of extracted cell protein). This was the only MPS I cell line, from a group of 23 MPS I patients, that contained greater than 7% of the mean level of α-l-iduronidase protein detected in normal controls. Cell line 2827 had very low α-l-iduronidase activity toward the fluorogenic substrate 4-methylumbelliferyl-α-l-iduronide, and a radiolabeled disaccharide substrate derived from heparin. Maturation studies of α-l-iduronidase in cell line 2827 showed apparently normal levels of α-l-iduronidase synthesis with delayed processing to the mature form. Subcellular fractionation experiments demonstrated α-l-iduronidase protein in lysosomal-enriched fractions isolated from cell line 2827, suggesting a normal cell distribution and supporting the proposed delayed processing. It is proposed that the MPS I patient described has an α-l-iduronidase gene mutation which affects both the active site and post-translational processing of the enzyme. This mutation must be structurally conservative because it does not result in instability either during maturation or in the lysosome.

UR - http://www.scopus.com/inward/record.url?scp=0026623026&partnerID=8YFLogxK

U2 - 10.1016/0885-4505(92)90028-W

DO - 10.1016/0885-4505(92)90028-W

M3 - Article

VL - 47

SP - 211

EP - 220

JO - Biochemical Medicine and Metabolic Biology

JF - Biochemical Medicine and Metabolic Biology

SN - 0885-4505

IS - 3

ER -