Immunological Characterization of Honey Proteins and Identification of MRJP 1 as an IgE-Binding Protein

We encountered a fourth case of honey allergy in Japan. We characterized and identified the IgE-binding proteins in honey using the serum of a honey-allergenic patient. Immunoblot analysis revealed that IgE in the patient serum specifically bound to four proteins in each honey sample. At least three of these IgE-binding proteins were N-linked glycoproteins. To identify the 60-kDa IgE-binding protein in dandelion honey, the N-terminal sequences of the fragmented protein were analyzed, revealing the protein to be major royal jelly protein 1 (MRJP 1). Three IgE-binding proteins removed of N-linked oligosaccharide showed a large reduction in IgE-binding activity as compared with the intact protein. This suggests that the carbohydrates in the IgE-binding proteins are a major epitope for patient IgE.     

Properties of the selenium-containing moiety of nicotinic acid hydroxylase from Clostridium barkeri

The nicotinic acid hydroxylase from Clostridium barkeri is a selenoenzyme, as evidenced by the copurification of selenium with enzyme activity. This conclusion is supported by data showing a 23-fold increase in nicotinic acid hydroxylase activity when C. barkeri was cultured in media supplemented with selenium. A labile, selenium-containing compound was released from the native protein by treatment with either chaotropic agents and heat or by heating alone. A stable selenium compound was formed when the enzyme was alkylated prior to denaturation. This compound had the same chromatographic properties as dialykyl selenide in a number of systems. The formation of dialkyl selenide upon alkylation is not consistent with the selenium moiety being selenocysteine. Thus, nicotinic acid hydroxylase represents a new type of selenoenzyme.     

Molecular genetics of cell death in the nematode Caenorhabditis elegans

In C. elegans, cell death can be readily studied at the cellular, genetic, and molecular levels. Two types of death have been characterized in this nematode: (1) programmed cell death, which occurs as a normal component in development; and (2) pathological cell death which occurs aberrantly as a consequence of mutation. Analysis of mutations that disrupt programmed cell death in various ways has defined a genetic pathway for programmed cell death which includes genes that perform such functions as the determination of which cells die, the execution of cell death, the engulfment of cell corpses, and the digestion of DNA from dead cells. Molecular analysis is providing insightinto the nature of the molecules that function in these aspects of programmed cell death. Characterization of some genes that mutate to induce abnormal cell death has defined a novel gene family called degenerins that encode putative membrane proteins. Dominant alleles of at least two degenerin genes, mec-4 and deg-1, can cause cellular swelling and late onset neurodegeneration of specific groups of cells. © 1992 John Wiley & Sons, Inc.     

Grouped sequential exploitation of food patches in a flock feeder,the feral pigeon

Feral and laboratory flocks of rock doves ($\text{Columba}$$\text{livia}$) show a pattern of grouped sequential exploitation when simultaneously presented with two dispersed, depleting patches of seed. This behavior contrasts with the ideal free distribution pattern shown when patches are small and concentrated. Grouped sequential exploitation consists of two phases: all pigeons first land together and feed at one patch, then leave one by one for the other patch. Departure times of individuals for the second patch are correlated with feeding rate at patch 1, which is in turn correlated with position in the dominance hierarchy. The decision to switch from patch 1 to patch 2 improves individual feeding rates in all cases, but is done slightly later than it should according to optimal foraging theory.     

Animal models for respiratory chain disease

Elucidation of the pathogenesis in respiratory chain diseases is of great importance for developing specific treatments. The limitations inherent to the use of patient material make studies of human tissues often difficult and the mouse has therefore emerged as a suitable model organism for studies of respiratory chain diseases. In this review, we present an overview of the field and discuss in depth a few examples of animal models reproducing pathology of human disease with primary and secondary respiratory chain involvement.     

Fibrinogen and fibrin in strong magnetic fields. Complementary results and discussion

When fibrin polymerizes in a strong magnetic field, it can be highly oriented. The structural diffraction study of the oriented polymer becomes thus possible. The magnetic birefringence can also be used to study the development of the polymer Fibrinogen in solution is weakly oriented in high magnetic fields. In this work we present complementary results and discussion. The validity of the comparison of the orientation parameters of fibrinogen and fibrin with those of other orientable known biological structures is discussed. The orientation of fibrin formed from fibrin monomer solution is compared to that of fibrin formed by the action of thrombin on fibrinogen. The conditions to obtain highly oriented fibrin gels suitable for three dimensional structure studies are also briefly discussed.     

Identification of Tumor Antigens in the HLA Peptidome of Patient-derived Xenograft Tumors in Mouse

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Highlights

• •Sufficient tumor tissues are often unavailable large HLA peptidome discovery.
• •Using patient derived xenograft (PDX) tumors can overcome this limitation.
• •The large PDX HLA peptidomes expand significantly those of the original biopsies.
• •The HLA peptidomes of the PDX tumors included many tumor antigens.