The roles of enteric bacterial sialidase, sialateO-acetyl esterase and glycosulfatase in the degradation of human colonic mucin

Corfield, Anthony P.; Wagner, Susan A.; O'donnell, L. J. D.; Durdey, P.; Mountford, R. A.; Clamp, John R.

doi:10.1007/bf00731190

Cited by 105 publications

(75 citation statements)

References 28 publications

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“…There is evidence that this sulfation of mucins makes them less susceptible to degradation by bacterial glycosidases, and thus the protective barrier is thought to remain more intact (7,14,16,25). However, some bacteria possess mucin-desulfating sulfatases which desulfate sulfomucin, allowing glycosidases to access and act on the mucins.…”

mentioning

confidence: 99%

A Novel Mechanism for Desulfation of Mucin: Identification and Cloning of a Mucin-Desulfating Glycosidase (Sulfoglycosidase) from Prevotella Strain RS2

et al. 2005

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A novel enzyme which may be important in mucin degradation has been discovered in the mucin-utilizing anaerobe Prevotella strain RS2. This enzyme cleaves terminal 2-acetamido-2-deoxy-␤-D-glucopyranoside 6-sulfate (6-SO 3 -GlcNAc) residues from sulfomucin and from the model substrate 4-nitrophenyl 2-acetamido-2-deoxy-␤-D-glucopyranoside 6-sodium sulfate. The existence of this mucin-desulfating glycosidase (sulfoglycosidase) suggests an alternative mechanism by which this bacterium may desulfate sulfomucins, by glycosidic removal of a sulfated sugar from mucin oligosaccharide chains. Previously, mucin desulfation was thought to take place by the action of a specific desulfating enzyme, which then allowed glycosidases to remove desulfated sugar. Sulfate removal from sulfomucins is thought to be a rate-limiting step in mucin degradation by bacteria in the regions of the digestive tract with a significant bacterial flora. The sulfoglycosidase was induced by growth of the Prevotella strain on mucin and was purified 284-fold from periplasmic extracts. Tryptic digestion and sequencing of peptides from the 100-kDa protein enabled the sulfoglycosidase gene to be cloned and sequenced. Active recombinant enzyme was made in an Escherichia coli expression system. The sulfoglycosidase shows sequence similarity to hexosaminidases. The only other enzyme that has been shown to remove 6-SO 3 -GlcNAc from glycoside substrates is the human lysosomal enzyme ␤-N-acetylhexosaminidase A, point mutations in which cause the inheritable, lysosomal storage disorder Tay-Sachs disease. The human enzyme removes GlcNAc from glycoside substrates also, in contrast to the Prevotella enzyme, which acts on a nonsulfated substrate at a rate that is only 1% of the rate observed with a sulfated substrate.

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confidence: 99%

A Novel Mechanism for Desulfation of Mucin: Identification and Cloning of a Mucin-Desulfating Glycosidase (Sulfoglycosidase) from Prevotella Strain RS2

et al. 2005

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“…Heavily sulfated mucins (sulfomucins) have many of the general lubricating and barrier functions of mucins with lower sulfate levels. There is accumulating evidence that sulfomucins may, in addition, rate-limit mucin degradation by mucin-degrading bacterial enzymes (4,7,13,15,18,24,26,27), and this role is thought to be particularly important in the colon, where approximately 10 14 bacterial cells are located (10). There have been reports of mucin-desulfating sulfatases that partially remove the sulfate from sulfomucin in a number of bacteria from the mouth, stomach, and colon and in feces.…”

mentioning

confidence: 99%

“…There have been reports of mucin-desulfating sulfatases that partially remove the sulfate from sulfomucin in a number of bacteria from the mouth, stomach, and colon and in feces. The effect of such sulfatases is to increase the susceptibility of the mucin to degradation by other mucin-degrading enzymes (4,27). Elevated levels of bacterial mucin-desulfating sulfatases are found in feces of patients with ulcerative colitis (26).…”

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confidence: 99%

Cloning of a Mucin-Desulfating Sulfatase Gene from Prevotella Strain RS2 and Its Expression Using a Bacteroides Recombinant System

et al. 2000

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A gene encoding the mucin-desulfating sulfatase in Prevotella strain RS2 has been cloned, sequenced, and expressed in an active form. A 600-bp PCR product generated using primers designed from amino acid sequence data was used to isolate a 5,058-bp genomic DNA fragment containing the mucin-desulfating sulfatase gene. A 1,551-bp open reading frame encoding the sulfatase proprotein was identified, and the deduced 517-amino-acid protein minus its signal sequence corresponded well with the published mass of 58 kDa estimated by denaturing gel electrophoresis. The sulfatase sequence showed homology to aryl-and nonarylsulfatases with different substrate specificities from the sulfatases of other organisms. No sulfatase activity could be detected when the sulfatase gene was cloned into Escherichia coli expression vectors. However, cloning the gene into a Bacteroides expression vector did produce active sulfatase. This is the first mucin-desulfating sulfatase to be sequenced and expressed. A second open reading frame (1,257 bp) was identified immediately upstream from the sulfatase gene, coding in the opposite direction. Its sequence has close homology to iron-sulfur proteins that posttranslationally modify other sulfatases. By analogy, this protein is predicted to catalyze the modification of a serine group to a formylglycine group at the active center of the mucin-desulfating sulfatase, which is necessary for enzymatic activity.Mucins are high-molecular-weight glycoproteins which form the structural component of the protective mucus gel layer at the surfaces of the gastrointestinal, respiratory, and female genital tracts. Colonic mucin, particularly in the proximal region, contains significant levels of sulfate covalently bound to the mucin oligosaccharide chains, and levels of 2.0 to 6.5 g of sulfate per 100 g of mucin have been found (9, 17). Heavily sulfated mucins (sulfomucins) have many of the general lubricating and barrier functions of mucins with lower sulfate levels. There is accumulating evidence that sulfomucins may, in addition, rate-limit mucin degradation by mucin-degrading bacterial enzymes (4,7,13,15,18,24,26,27), and this role is thought to be particularly important in the colon, where approximately 10 14 bacterial cells are located (10). There have been reports of mucin-desulfating sulfatases that partially remove the sulfate from sulfomucin in a number of bacteria from the mouth, stomach, and colon and in feces. The effect of such sulfatases is to increase the susceptibility of the mucin to degradation by other mucin-degrading enzymes (4, 27). Elevated levels of bacterial mucin-desulfating sulfatases are found in feces of patients with ulcerative colitis (26). The sulfated sugar specificity of these fecal sulfatases, the number of different types present, the bacterial origin of the elevated levels, and the conditions which regulate bacterial production of such enzymes are unknown. The types of mucin-desulfating sulfatases that might be predicted include sulfatases specific for galactose-3-sulfate, g...

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“…The faecal extracts from ulcerative colitisaffected patients had a higher sialate 0-acetyl esterase and glycosulfatase activity, while mucin sialidase activity was unchanged. Moreover, mucin was degraded more efficiently and rapidly in patients than in healthy controls [4].…”

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confidence: 91%

Selective in vitro degradation of the sialylated fraction of germ-free rat mucins by the caecal flora of the rat

Fontaine

Meslin²,

Doré³

1998

Reprod. Nutr. Dev.

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-Mucins, which are synthesized throughout the gastrointestinal tract, may be degraded by the microflora of the large intestine. The present study was undertaken to determine the differential fate of the various types of mucins. Mucins from germ-free rats were incubated in vitro in the presence of whole caecal flora from the conventional rat. Neutral, acidic and acidic sulphated mucins were spectrophotometrically assayed over time upon anaerobic incubation. Sialylated mucins were more rapidly degraded (90 %)

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The roles of enteric bacterial sialidase, sialateO-acetyl esterase and glycosulfatase in the degradation of human colonic mucin

Cited by 105 publications

References 28 publications

A Novel Mechanism for Desulfation of Mucin: Identification and Cloning of a Mucin-Desulfating Glycosidase (Sulfoglycosidase) from Prevotella Strain RS2

A Novel Mechanism for Desulfation of Mucin: Identification and Cloning of a Mucin-Desulfating Glycosidase (Sulfoglycosidase) from Prevotella Strain RS2

Cloning of a Mucin-Desulfating Sulfatase Gene from Prevotella Strain RS2 and Its Expression Using a Bacteroides Recombinant System

Selective in vitro degradation of the sialylated fraction of germ-free rat mucins by the caecal flora of the rat

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