title: [Neuraminidase forms in human chorion].
abstract: Detection of various forms of neuraminidase from human chorion was carried out by means of evaluation of the enzyme stability of freezing-thawing and of its ability to bind lectin. Freezing of chorion in liquid nitrogen enabled to find in the tissue labile neuraminidase, which occurred in soluble fraction as well as the more stable enzyme form, precipitated with cell particles. At the same time, properties of soluble and membrane-bound neuraminidases, involving pH optima and specificity towards synthetic substrates, were similar. The precipitated neuraminidase from human chorion consisted of two forms, bound- and unbound with Con A-Sepharose. Both these forms exhibited similar pH optima and Km values but were dissimilar in their stability. The neuraminidases from human chorion, dissimilar in their property of lectin-binding, resembled the enzymes from human leukocytes. Besides, beta-galactosidases from both human chorion and leukocytes were bound with Con A-Sepharose practically completely.
authors.forename: N A
authors.initials: NA
authors.lastname: Petushkova
mesh_terms: D002823:Chorion / Q000201:enzymology*; D005347:Fibroblasts / Q000201:enzymology; D005615:Freezing; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007527:Isoenzymes / Q000302:isolation & purification*; D007962:Leukocytes / Q000201:enzymology; D009439:Neuraminidase / Q000302:isolation & purification*; D012995:Solubility
chemical_list: D007527:Isoenzymes; D009439:Neuraminidase
vernacular_title: K voprosu o formakh neĭraminidazy khoriona cheloveka.