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PubMed · 12951527

Interaction between acidic polysaccharides and proteins.

Kenjiro Tadera·Yuji Minami·Miki Chohchi
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Abstract

There was an ionic interaction between acidic polysaccharides (APS) and proteins at the pH range in which APS were negatively charged and proteins were positively charged, and in enzymes the interaction was detected as a change in the enzyme activity. At pH 4.7, acid phosphatase (pI, 5.4), alpha-glucosidase (pI, 5.7), and beta-glucosidase (pI, 7.3) were inhibited by APS to various extents. On the other hand, alpha-glucosidase and alkaline phosphatase (pI, 4.5) were not inhibited by APS at pH 6.8 and 9.8, respectively, most of these two enzymes being negatively charged at the respective pHs. Sulfated polysaccharides combined with hemoglobin (pI, 6.8 to approximately 7.0) by an ionic bond at pH 2 to make hemoglobin unsusceptible to proteolysis by pepsin, but polyuronides which were not charged at this pH did not affect hydrolysis of hemoglobin.

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Acid PhosphataseAlkaline PhosphataseAnimalsCattleEnzyme InhibitorsEnzymesGlycoside Hydrolase InhibitorsHemoglobinsHydrogen-Ion ConcentrationPepsin APolysaccharidesPrunusStomachSwineYeastsalpha-Glucosidasesbeta-GlucosidaseJournal Article

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Kenjiro Tadera, Yuji Minami, Miki Chohchi. 2003. Interaction between acidic polysaccharides and proteins.. https://doi.org/10.1271/bbb.67.1840

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