The word crosslinking implies durable combination of (usually large) distinct elements at specific places to create a new entity that has different properties as a result of the union. In the case of proteins, such crosslinking often results in important changes in chemical, functional, nutritional, and biomedical properties, besides physical properties simply related to molecular size and shape. (Nucleic acids, carbohydrates, and other biopolymers are correspondingly affected.) Since proteins are ubiquitous, the consequences of their crosslinking are widespread and often profound. Scientists from many disciplines including organic chemistry, bio­ chemistry, protein chemistry, food science, nutrition, radiation biology, pharmacology, physiology, medicine, and dentistry are, therefore, minutely interested in protein crosslinking reactions and their implications. Because protein crosslinking encompasses so many disciplines, in organizing the Symposium on Nutritional and Biochemical Conse­ quences of Protein Crosslinking sponsored by the Protein Subdivi­ sion of the Division of Agricultural and Food Chemistry of the American Chemical Society, I sought participants with the broadest possible range of interests, yet with a common concern for theore­ tical and practical aspects of protein crosslinking. An important function of a symposium is to catalyze progress by bringing together ideas and experiences needed for interaction among different, yet related disciplines. To my pleasant surprise, nearly everyone invited came to San Francisco to participate.

Inhalt

of Part A.- 1. Biologically Important Thiol-Disulfide Reactions and the Role of Cyst(e)ine in Proteins: an Evolutionary Perspective.- 2. Disulfide Crosslinks and the Specificity of Protein Turnover in Plants.- 3. Protein Thiol-Disulfide Interchange and Interfacing with Biological Systems.- 4. on the Mechanism of Renaturation of Proteins Containing Disulfide Bonds.- 5. Disulfide Bonds: Key to Wheat Protein Functionality.- 6. Chemical Strategy for Studying the Antigenic Structures of Disulfide-Containing Proteins: Hen Egg-White Lysozyme as a Model.- 7. Crosslinking of Antibody Molecules by Bifunctional Antigens.- 8. Modification of the Biological Properties of Plant Lectins by Chemical Crosslinking.- 9. Introduction of Artificial Crosslinks Into Proteins.- 10. Synthesis and Application of new Bifunctional Reagents.- 11. Synthesis and Application of Cleavable and Hydrophilic Crosslinking Reagents.- 12. Comparison of Hydrophobic and Strongly Hydrophilic Cleavable Crosslinking Reagents in Intermolecular Bond Formation in Aggregates of Proteins Or Protein-Rna.- 13. Crosslinking of Ribosomes by Cleavable Bifunctional Mercaptoimidates.- 14. on the Introduction of Disulfide Crosslinks Into Fibrous Proteins and Bovine Serum Albumin.- 15. Thiolation and Disulfide Cross-Linking of Insulin to Form Mac Romolecules of Potential Therapeutic Value.- 16. Crosslinked Insulins: Preparation, Properties and Applications.- 17. the Enzymic Derivation of Citrulline Residues From Arginine Residues in Situ During the Biosynthesis of Hair Proteins That Are Cross-Linked by Isopeptide Bonds.- 18. Thermodynamics of Crosslinks.- 19. Physical and Chemical Consequences of Keratin Crosslinking, with Application to the Determination of Crosslink Density.- 20. An X-Ray Diffraction Study of Thermally-Induced Structural Changes in ?-Keratin.- 21. Introduction of new Crosslinks Into Proteins.- 22. Comparison of Wool Reactions with Selected Monoand Bifunctional Reagents.- 23. the effects of Ethylene Glycol on Wool Fibers.- 24. Protein: Polyanion Interactions. Studies of the Trehalose-P Synthetase as a Model System.- 25. Kinetic Studies of Immobilized ?-Chymotrypsin in Apolar Solvents.- 26. Factors Affecting Cyanoborohydride Reduction of Aromatic Schiff'S Bases in Proteins.- 27. Chemistry of the Crosslinking of Collagen During Tanning.- 28. Chemical Modification of Collagen and the effects on Enzyme-Binding: Mechanistic Considerations.- 29. Strategies in the Racemization-Free Synthesis of Polytripeptide Models of Collagen.- 30. Conformational Properties of Polypeptide Models of Collagen.- 31. Ionizing Radiation-Induced Crosslinking in Proteins.- 32. Peroxydisulfate Anion-Induced Crosslinking of Proteins.- 33. Cross Linking in the Radiolysis of some Enzymes and Related Proteins.- 34. Isolation and Characterization of Stable Protein-DNA Adducts Induced in Chromatin by Ultraviolet Light.- 35. Identification of Binding Sites of the E. Coli Ribosome by Affinity Labeling.- 36. Photoinduced Nucleic Acid-Protein Crosslinkage in Ribosomes and Ribosome Complexes.- 37. Crosslinking of Nucleic Acids and Proteins by Bisulfite.- 38. Crosslinking of Amino Acids by Formaldehyde. Preparation and 13C Nmr Spectra of Model Compounds.- 39. Electron Microscopy of An Oligomeric Protein Stabilized by Poly Functional Cross-Linking.- 40. Fish Myofibrillar Protein and Lipid Interaction in Aqueous Media as Derived by Isotope Labeling, Sucrose Gradient Centrifugation, Polyacrylamide Electrophoresis and Electron Paramagnetic Resonance.- 41. Gas-Liquid Chromatography and Mass Spectrometry of Lanthionine, Lysinoalanine, and S-Carboxy-Ethylcysteine.- 42. Mass Spectra of Cysteine Derivatives.- 43. a Nuclear Magnetic Double Resonance Study of N-?-Bis(?'-Chloroethyl)Phosphonylethyl-DL-Phenylalanine.