Search results for "Killer Factors"
showing 4 items of 14 documents
Comparison of the killer toxin of several yeasts and the purification of a toxin of type K2
1984
A total of 13 killer toxin producing strains belonging to the genera Saccharomyces, Candida and Pichia were tested against each other and against a sensitive yeast strain. Based on the activity of the toxins 4 different toxins of Saccharomyces cerevisiae, 2 different toxins of Pichia and one toxin of Candida were recognized. The culture filtrate of Pichia and Candida showed a much smaller activity than the strains of Saccharomyces. Extracellular killer toxins of 3 types of Saccharomyces were concentrated and partially purified. The pH optimum and the isoelectric point were determined. The killer toxins of S. cerevisiae strain NCYC 738, strain 399 and strain 28 were glycoproteins and had a m…
Investigation of a Killer Strain of Zygosaccharomyces Bailii
1993
Summary: The yeast Zygosaccharomyces bailii strain 412 was found to liberate a killer toxin (KT412) lethal to sensitive strains of Saccharomyces cerevisiae and Candida glabrata. Culture supernatants of the killer strain were concentrated by ultrafiltration and the extracellular protein was purified by gel filtration and ion-exchange chromatography. Gel filtration and SDS-PAGE of the electrophoretically homogeneous killer protein indicated an apparent molecular mass of 10 kDa. The killer toxin KT412 is probably not glycosylated since it did not show any detectable carbohydrate structures. KT412 was bound to sensitive but not to resistant yeast cells. The mannan, and not the glucan, fraction …
Sequence of the M28 dsRNA: Preprotoxin Is Processed to an α/β Heterodimeric Protein Toxin
1995
The killer and immunity phenotypes of K28 killer strains of Saccharomyces cerevisiae are determined by the 1.75-kb M28 dsRNA virus. In the plus strand, M28p, the K28 preprotoxin gene, comprises bases 13-1047 and is followed, after an additional 85 bases, by a 63-bp poly(A) sequence and a 553-base 3'-sequence. This 3'-sequence contains two potential stem-loop structures predicted to bind the L-A encoded cap-pol protein, initiating encapsidation; high-level expression results in curing of M1 dsRNA. Expression of M28p confers the complete K28 killer and immunity phenotype on a cell lacking M28 dsRNA. K28 toxin is a disulfide-bonded heterodimer of alpha (10.5 kDa) and beta (11 kDa) components w…
Yeast Killer Toxin-Like Candidacidal Ab6 Antibodies Elicited through the Manipulation of the Idiotypic Cascade
2014
A mouse anti-anti-anti-idiotypic (Id) IgM monoclonal antibody (mAb K20, Ab4), functionally mimicking a Wyckerhamomyces anomalus (Pichia anomala) killer toxin (KT) characterized by fungicidal activity against yeasts presenting specific cell wall receptors (KTR) mainly constituted by β-1,3-glucan, was produced from animals presenting anti-KT Abs (Ab3) following immunization with a rat IgM anti-Id KT-like mAb (mAb K10, Ab2). MAb K10 was produced by immunization with a KT-neutralizing mAb (mAb KT4, Ab1) bearing the internal image of KTR. MAb K20, likewise mAb K10, proved to be fungicidal in vitro against KT-sensitive Candida albicans cells, an activity neutralized by mAb KT4, and was capable of…