objective: verotoxin is a member of shiga toxin family. this family contains ab protein toxins with an enzymatic (a) and a binding (b) compartment. cells that have receptor (gb3) are sensitive to cytotoxic effects of toxin. it has been shown that various tumor cells have gb3 receptor and are selectively sensitive to apoptotic effect of verotoxin. studies on tumor cell lines and laboratory anima...

a classical result of neumann characterizes the groups in which each subgroup has finitely many conjugates only as central-by-finite groups. if x is a class of groups, a group g is said to have x-conjugate classes of subgroups if g/coreg(ng(h)) 2 x for each subgroup h of g. here we study groups which have soluble minimax conjugate classes of subgroups, giving a description in terms of g/z(g). w...

An enzyme-linked immunosorbent assay (ELISA) is described for Pseudomonas aeruginosa exotoxin A. A double antibody sandwich method was used, employing polyvinyl microtiter plates as the solid phase, a primary coat of monospecific rabbit antitoxin serum, an outer layer composed of a horseradish peroxidase-sheep antitoxin immunoglobulin G conjugate, and an ortho-phenylene-diamine substrate. Absor...

Mutants of the human KB carcinoma cell line resistant to a cytotoxic conjugate of epidermal growth factor (EGF) and Pseudomonas exotoxin (PE) were selected. EGF-PE and the drug verapamil, which enhanced EGF-PE cytotoxicity, were used in the selection process. These mutants also showed some cross-resistance to PE. All of the EGF-PE resistant variants displayed lower levels of 125I-EGF binding, 2...

Mycothiol (MSH), a functional analogue of glutathione (GSH) that is found exclusively in actinomycetes, reacts with electrophiles and toxins to form MSH-toxin conjugates. Mycothiol S-conjugate amidase (Mca) then catalyzes the hydrolysis of an amide bond in the S conjugates, producing a mercapturic acid of the toxin, which is excreted from the bacterium, and glucosaminyl inositol, which is recyc...

Previously, a quantitative analysis that related protein synthesis inhibition of transferrin-toxin conjugates to the cellular trafficking of transferrin was proposed (P.T. Yazdi and R. M. Murphy, Cancer Res., 54: 6387-6394, 1994). Here, this work is extended to evaluate cellular trafficking of anti-transferrin receptor antibodies and protein synthesis inhibition kinetics of immunotoxins constru...

Murine polyclonal antibodies reactive to the lantibiotic bacteriocin nisin A (nisA) have been produced by immunization with nisA-cholera toxin and nisA-keyhole limpet hemocyanin (nisA-KLH) conjugates. Mice immunized with nisA-cholera toxin developed nisA-specific antibodies with low relative affinities and poor sensitivities, while the immunization of mice with nisA-KLH conjugates resulted in t...

Livestock ingest numerous potentially toxic compounds, including natural plant and fungal metabolites, insect chemical defenses, human-made environmental pollutants, and therapeutic drugs. In turn, animals evolved physiological mechanisms to protect themselves from these ingested toxins. Enzymes have been described that first activate toxins cytochrome P-450 and then conjugate the compounds (gl...

The biochemical and biological characteristics of CRM(197) are reviewed. Polysaccharide protein conjugate vaccines represent an important technological advancement that allowed for protection against dangerous diseases in vulnerable populations such as infants. The first carrier proteins, diphtheria and tetanus toxoids, were chosen in the context of an extensive body of information describing t...

Here we describe a new approach for tumor targeting in which augmented concentrations of Fe(II) in cancer cells and/or the tumor microenvironment triggers drug release from an Fe(II)-reactive prodrug conjugate. The 1,2,4-trioxolane scaffold developed to enable this approach can in principle be applied to a broad range of cancer therapeutics and is illustrated here with Fe(II)-targeted forms of ...