Five novel lectin isoforms, Volvariella volvacea (VV) lectins, designated VVA, VVB, VVC, VVD & VVE, were isolated and purified from the fruiting bodies of an edible mushroom, Volvariella volvacea , by ion-exchange chromatographies in a FPLC system. Their molecular masses are very close, as measured by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF/MS); they are 12740, 12737, 12709, 12708 & 12707 Da for VVA, VVB, VVC, VVD & VVE, respectively, but the pI values between VVA and the others show distinct differences; the pI value of VVA is around 6.7 and the others are much closer to each other (higher than pI 9.3). Their sugar-binding specificities are thyroglobulin, N-acetylneuramic acid and galacturonic acid. The mitogenic activities of VVA and VVE with distinct pI values were measured using [methyl -3H]thymidine (3H-TdR) incorporation assays, nucleic acid sequence by rapid amplification of cDNA ends analysis, amino acid sequencing and molecular masses by MALDI-TOF/MS and gel electrophoresis, respectively. / VVA and VVE share 98.2% amino acid sequence similarities. Both VVA and VVE are potent mitogens toward mouse CD3+ & CD4 + T-cells, which were mediated through a calcium-dependent activation signaling pathway (Sze et al., 2004). VVA is slightly more effective than VVE in the induction of T cell activation and proliferation, as demonstrated by 3H-TdR incorporation assays, cell flow cytometry for calcium ion mobilization, immunoblotting blot analysis for tyrosine phosphorylation of Lck proteins and Lck shift (p60lck protein), and two dimensional gel electrophoresis for up-regulated proteins. The gene encoding VV lectin was cloned and characterized. The recombinant protein possessed hemagglutinating activity and mitogenic activity, as demonstrated by hemagglutination assays and 3H-TdR incorporation assays respectively. The endoproteinase Arg-C-digested VVA retained the mitogenic activity but lost the hemagglutinating activity, indicating that the mitogenic activity of VVA is not only dependent on the dimerization and tertiary structure of the protein (Paaventhan et al., 2003; Lin et al., 1997), but also on the primary structure of unique amino acid sequences. These endoproteinase fragments have also been used for study of structure-function relationship. / Sze Cho Wing. / "July 2004." / Adviser: Ken W. K. Liu. / Source: Dissertation Abstracts International, Volume: 67-01, Section: B, page: 0171. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (p. 156-189). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.

Thesis (M.Sc. (Microbiology)) -- University of Limpopo, 2011 / Lectins are among a large number of proteins produced by mushrooms. Mushroom lectins with important biological functions have been isolated and studied. However, none of the studies were reported on lectins isolated from mushrooms indigenous to southern Africa. A galactose-specific lectin from one of the common mushroom species in southern Africa, Schizophyllum commune, was isolated and characterized. Initially, twenty mushroom samples were collected and their crude extracts screened for lectin activities. Assays involved in the screening procedures included heamagglutination, carbohydrate inhibition, enzyme linked glycoprotein (ELGA) and various stability assays. Four different mushroom samples exhibited positive lectin activities with varying stabilities towards thermal treatment and susceptibility to proteolytic degradation. Further screening assays resulted in ZHR1 being selected for identification and purification of the lectin. This was due to its ability to agglutinate rabbit erythrocytes. In addition to its activity being destroyed after 3 hours of treatment with trypsin-NIPAAM conjugate, the activity of this lectin was also completely destroyed after an hour incubation in boiling water. In contrast to other mushroom extracts assayed, heamagglutination activity of the crude extract of ZHR1 was not inhibited by glycoproteins only but also by the sugars such as galactose, lactose and mannose. ZHR1 was identified as S. commune. S. commune lectin (ScL) was purified using affinity chromatography on a fetuin-agarose column and further purified using gel-filtration chromatography on Biogel P-100 column. ScL was characterized as a glycosylated, galactose-specific dimeric lectin with a molecular weight of approximately 32 and 33 kDa. ScL is a thermolabile lectin which loses its activity as early as 5 minutes after being incubated at 60°C. Anti-ScL antibodies, to be employed in screening for the presence of ScL in the protein extracts, were developed in the rabbits and their interaction with ScL was detected using the double immunodiffusion assays whereas their specificity towards the lectin was detected using Western blot. ScL is one of the first mushroom lectins to be isolated and studied in southern African region. If the lectin is found to be exhibiting important biological functions, ScL can be of commercial importance in the region.

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by Poon Suet Ping, Cycles. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1981. / Bibliography: leaves 117-129.

by Linda Shiou-Mei Ooi. / Thesis (Ph.D.)--Chinese University of Hong Kong, 1998. / Includes bibliographical references (p. 118-126). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.

Thesis (Ph. D.)--Swedish University of Agricultural Sciences, 2001. / Includes bibliographical references.

Thesis (M. Phil.)--University of Hong Kong, 2001. / Includes bibliographical references (leaves 93-119).