We have now reached our sixth volume in a series which has somewhat unintentionally become an annual event. While we still intend to produce a volume only if a suitable number of excellent chapters in the forefront of biological magnetic resonance are available, our philosophy is to present a pedagogical yet critical description and review of selected topics in mag netic resonance of current interest to the community of biomedical scien tists. This volume fulfills our goals well. As always, we open the volume with a chapter which directly addresses an in vivo biological problem: Phil Bolton's presentation of new techniques in measuring 31 P NMR in cells. Lenkinski's chapter on the theory and applications of lanthanides in protein studies covers the details, highlights, and pitfalls of analysis of these com plexes in biochemical NMR. Reed and Markham summarize the interpreta tion of EPR spectra of manganese in terms of structure and function of proteins and enzymes. Dalton and colleagues describe the applications to biological problems of the relatively new capability of time domain ESR. Finally, we are pleased to offer a departure from mainstream magnetic resonance with the comprehensive and stimulating chapter by Gus Maki on the theory, instrumentation, and applications of optically detected magnetic resonance.

Inhalt

1 Two-Dimensional Spectroscopy as a Conformational Probe of Cellular Phosphates.- 1. Introduction.- 2. Basic Principles of Heteronuclear Two-Dimensional NMR.- 3. Analysis of Heteronuclear Two-Dimensional NMR Spectra.- 4. Experimental and Instrumental Considerations.- 5. Range and Limitations of Heteronuclear Two-Dimensional NMR.- 6. Long-Range Spying: Relayed Transfer Spectroscopy.- 7. Heteronuclear Zero Quantum Spectroscopy.- 8. Future Applications and Developments.- References.- 2 Lanthanide Complexes of Peptides and Proteins.- 1. Introduction.- 2. Chemistry of the Lanthanide Ions.- 2.1. Ionic Radii and Hydration Numbers.- 2.2. Isostructurality of Lanthanide Complexes.- 2.3. Thermodynamics and Kinetics of Complex Formation.- 3. Theoretical Background.- 3.1. Chemical Exchange.- 3.2. Chemical Shifts.- 3.3. Relaxation Rates.- 3.4. Conformational Averaging.- 4. Proteins.- 4.1. Lysozyme.- 4.2. Carp Parvalbumin.- 5. Peptides.- 5.1. Angiotensin II.- 5.2. Neurohypophyseal Hormones.- 6. Conclusions.- References.- 3 EPR of Mn(II) Complexes with Enzymes and Other Proteins.- 1. Introduction.- 1.1. Electronic Configuration of Mn(II).- 1.2. Coordination Properties.- 2. EPR Properties of Mn(II).- 2.1. Introduction.- 2.2. The Superposition Model.- 2.3. Symmetry Considerations.- 2.4. Ligand Superhyperfine Coupling.- 3. Experimental Methods.- 4. The Spin Hamiltonian.- 5. Evaluation of ZFS Parameters.- 5.1. Larger Zero-Field Splittings.- 5.2. Magnetic Interactions between Mn(II) Ions.- 5.3. Dipolar Interactions.- 5.4. Exchange Interactions.- 6. Applications.- 6.1. Concanavalin A.- 6.2. Creatine Kinase.- 6.3. 3-Phosphoglycerate Kinase.- 6.4. Pyruvate Kinase.- 6.5. Pyruvate and Phosphate Dikinase.- 6.6. Glutamine Synthetase.- 6.7. Adenylosuccinate Synthetase.- 6.8. Enolase.- 6.9. S-Adenosylmethionine Synthetase.- 7. Summary and Prospects.- Appendix I: FORTRAN Program for Simulation of Mn(II) Powder EPR Spectra.- References.- 4 Biological Applications of Time Domain ESR.- 1. Introduction.- 2. Pulsed EPR Experiments.- 2.1. Measurement of Spin-Spin or Phase Memory Times.- 2.2. Measurement of Spin-Lattice Relaxation Times.- 2.3. Measurement of Spectral Diffusion Times.- 2.4. Measurement of Chemical Reaction Rates.- 2.5. Analysis of Electron Spin Echo Envelope Modulation (ESEEM or ESEM) and the Measurement of Hyperfine and Quadrupolar Interactions.- 2.6. ESE Studies of the Linear Electric Field Effect (LEFE).- 2.7. ESE Studies Employing Magnetic Field Gradients.- 3. Instrumentation.- 3.1. Spin Echo Spectrometers.- 3.2. Saturation Recovery Spectrometers.- 4. Comment On The Future Of Pulsed EPR Techniques.- References.- 5 Techniques, Theory, and Biological Applications of Optically Detected Magnetic Resonance (ODMR).- 1. Introduction.- 2. The Photoexcited Triplet State.- 2.1. Electron Magnetic Dipole-Dipole Interactions.- 2.2. Magnetic Resonance Transitions in Zero Field.- 2.3. Effects of an External Magnetic Field.- 2.4. Spin-Orbit Coupling.- 3. Theory and Methods of ODMR.- 3.1. Steady-State (Slow-Passage) Measurements.- 3.2. Transient ODMR Methods with Continuous Optical Pumping.- 3.3. Transient Measurements in the Absence of Optical Pumping.- 3.4. Methods for Obtaining the Relative Populations and ISC Rates.- 3.5. Multiple Resonance Methods.- 3.6. Linewidths in ODMR Spectra.- 4. Experimental Considerations.- 4.1. The Basic Spectrometer.- 4.2. Modifications for Kinetics Measurements.- 4.3. System Details.- 5. ODMR of Biologically Significant Molecules.- 5.1. Amino Acids, Peptides, and Proteins.- 5.2. The Nucleic Acids.- 5.3. Porphyrins and Photosynthetic Systems.- References.