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PubMed · 8146

Neutral alpha-mannosidase activity in human serum.

B Hultberg·P K Masson·S Sjöblad
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Abstract

Two types of alpha-mannosidase (alpha-D-mannoside mannohydrolase, EC 3.2.1.24) with neutral pH optima exist in serum. The activity with an optimum between pH 6.0 and 6.4 is similar to alpha-mannosidase C, described earlier in tissues. The second activity, with a pH optimum between pH 5.2 and 5.8 is the dominant form in serum. These two forms can be differentiated from each other by gel-filtration, chromatography on DEAE-cellulose or chromatography on Concanavalin-A Sepharose. Using the chromatographic techniques, the serum type neutral activity co-elutes with the acidic forms of the enzyme. However, these two forms can be easily distinguished by effect of pH, heating or inhibition by the substrate methyl-alpha-D-mannopyranoside. The presence of the serum type alpha-mannosidase activity is discussed with respect to mannosidosis, a lysosomal storage disease.

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DisaccharidasesHumansHydrogen-Ion ConcentrationIsoenzymesKineticsMannosidasesJournal Article

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B Hultberg, P K Masson, S Sjöblad. 1976-09-14. Neutral alpha-mannosidase activity in human serum.. https://doi.org/10.1016/0005-2744(76)90093-0

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