This detailed volume provides in-depth protocols for protein labeling techniques and applications, with an additional focus on general background information on the design and generation of the organic molecules used for the labeling step. Chapters provide protocols for labeling techniques and applications, with an additional focus on general background information on the design and generation of the organic molecules used for the labeling step. Written in the highly successful Methods in Molecular Biology series format, chapters include introductions to their respective topics, lists of the necessary materials and reagents, step-by-step, readily reproducible laboratory protocols, and tips on troubleshooting and avoiding known pitfalls. Authoritative and practical, Site-Specific Protein Labeling: Methods and Protocols provides a comprehensive overview on the most relevant and established labeling methodologies, and helps researchers to choose the most appropriate labeling method for their biological question.

This detailed volume provides in-depth protocols for protein labeling techniques and applications, with an additional focus on general background information on the design and generation of the organic molecules used for the labeling step. Chapters provide protocols for labeling techniques and applications, with an additional focus on general background information on the design and generation of the organic molecules used for the labeling step. Written in the highly successful Methods in Molecular Biology series format, chapters include introductions to their respective topics, lists of the necessary materials and reagents, step-by-step, readily reproducible laboratory protocols, and tips on troubleshooting and avoiding known pitfalls. Authoritative and practical, Site-Specific Protein Labeling: Methods and Protocols provides a comprehensive overview on the most relevant and established labeling methodologies, and helps researchers to choose the most appropriate labeling method for their biological question.

Technological improvements in the assays and equipment used for biological, biochemical, biophysical and microscopy purposes have ensured that methods for labeling of proteins with reporter molecules remain in high demand. Standard chemical labeling methods using entities that react with amino acid side chains lack the specificity to ensure precise placement of reporter groups. Genetic methods, although specific, lack the versatility afforded by chemical synthesis-most reporters are limited to protein sized domains or peptide tags to which corresponding antibody based reagents are available. The first portion of this work is devoted to the establishment of a system that allows for the site-specific labeling of proteins with a wide variety of chemically synthesized probes. This system exploits sortases, a class of bacterial transpeptidases, that recognize a small five amino acid tag genetically fused to the protein of interest and catalyze the formation of an amide bond between the protein to be studied and the probe. The second part of this thesis describes how this sortase mediated protein labeling method has been implemented to explore enzyme structure and function, improve the physical properties of therapeutic proteins, study glycoproteins important for innate immune responses in living cells (Appendix A), and visualize influenza glycoproteins in living, infected cells. Finally, a protocol is included for this system (Appendix B), which is both versatile and easy to establish in any lab. The synthetic chemistry demanded is minimal, requiring only standard, readily available reagents, making the system amenable to labs equipped for cell and molecular biology experiments.

Bioconjugate Techniques, 2nd Edition, is the essential guide to the modification and cross linking of biomolecules for use in research, diagnostics, and therapeutics. It provides highly detailed information on the chemistry, reagent systems, and practical applications for creating labeled or conjugate molecules. It also describes dozens of reactions with details on hundreds of commercially available reagents and the use of these reagents for modifying or cross linking peptides and proteins, sugars and polysaccharides, nucleic acids and oligonucleotides, lipids, and synthetic polymers. A one-stop source for proven methods and protocols for synthesizing bioconjugates in the lab Step-by-step presentation makes the book an ideal source for researchers who are less familiar with the synthesis of bioconjugates More than 600 figures that visually describe the complex reactions associated with the synthesis of bioconjugates Includes entirely new chapters on the latest areas in the field of bioconjugation as follows: Microparticles and nanoparticlesSilane coupling agentsDendrimers and dendronsChemoselective ligationQuantum dotsLanthanide chelatesCyanine dyesDiscrete PEG compoundsBuckyballs,fullerenes, and carbon nanotubesMass tags and isotope tagsBioconjugation in the study of protein interactions

How to synthesize native and modified proteins in the test tube With contributions from a panel of experts representing a range of disciplines, Total Chemical Synthesis of Proteins presents a carefully curated collection of synthetic approaches and strategies for the total synthesis of native and modified proteins. Comprehensive in scope, this important reference explores the three main chemoselective ligation methods for assembling unprotected peptide segments, including native chemical ligation (NCL). It includes information on synthetic strategies for the complex polypeptides that constitute glycoproteins, sulfoproteins, and membrane proteins, as well as their characterization. In addition, important areas of application for total protein synthesis are detailed, such as protein crystallography, protein engineering, and biomedical research. The authors also discuss the synthetic challenges that remain to be addressed. This unmatched resource: Contains valuable insights from the pioneers in the field of chemical protein synthesis Presents proven synthetic approaches for a range of protein families Explores key applications of precisely controlled protein synthesis, including novel diagnostics and therapeutics Written for organic chemists, biochemists, biotechnologists, and molecular biologists, Total Chemical Synthesis of Proteins provides key knowledge for everyone venturing into the burgeoning field of protein design and synthetic biology.

Personalized medicine employing patient-based tailor-made therapeutic drugs is taking over treatment paradigms in a variety of ?elds in oncology and the central nervous system. The success of such therapies is mainly dependent on ef?cacious therapeutic drugs and a selective imaging probe for identi?cation of potential responders as well as therapy monitoring for an early bene?t assessment. Molecular imaging (MI) is based on the selective and speci?c interaction of a molecular probe with a biological target which is visualized through nuclear, magnetic resonance, near infrared or other methods. Therefore it is the method of choice for patient selection and therapy monitoring as well as for speci?c e- point monitoring in modern drug development. PET (positron emitting tomography), a nuclear medical imaging modality, is ideally suited to produce three-dimensional images of various targets or processes. The rapidly increasing demand for highly selective probes for MI strongly pushes the development of new PET tracers and PET chemistry. ‘PET chemistry’ can be de?ned as the study of positron-emitting compounds regarding their synthesis, structure, composition, reactivity, nuclear properties and processes and their properties in natural and - natural environments. In practice PET chemistry is strongly in?uenced by the unique properties of the radioisotopes used (e. g. , half-life, che- cal reactivity, etc. ) and integrates scienti?c aspects of nuclear-, organic-, inorganic- and biochemistry.

Presenting a wide array of information on chemical ligation – one of the more powerful tools for protein and peptide synthesis – this book helps readers understand key methodologies and applications that protein therapeutic synthesis, drug discovery, and molecular imaging. • Moves from fundamental to applied aspects, so that novice readers can follow the entire book and apply these reactions in the lab • Presents a wide array of information on chemical ligation reactions, otherwise scattered across the literature, into one source • Features comprehensive and multidisciplinary coverage that goes from basics to advanced topics • Helps researchers choose the right chemical ligation technique for their needs

Chemical fluorophores have superior photophysical properties to fluorescent proteins and are much smaller. However, in order to use these probes for live-cell protein imaging, highly specific labeling methods are required. Here, we will describe three efforts to re-engineer the E. coli enzyme, lipoic acid ligase (LplA), to catalyze the ligation of small-molecule probes onto recombinant proteins. We call this collection of methods the PRIME (PRobe Incorporation Mediated by Enzymes) methodologies. First, we describe the structure-guided mutagenesis of LplA and the identification of an LplA variant that can ligate a blue coumarin fluorophore onto a 13-amino acid LplA acceptor peptide (LAP2). This "coumarin ligase" can be used to image cellular proteins with high specificity, sensitivity, and minimal perturbation of the biology of the protein of interest. We also demonstrate how subpopulations of a protein of interest can be labeled using genetically targeted coumarin ligase. Second, we describe our attempts to use yeast display evolution and fluorescence activated cell sorting (FACS) to evolve a truncated LplA enzyme. The original truncated enzyme had severely decreased activity for LplA's natural substrate, lipoic acid. We created a 107 library of LplA mutants and, after four rounds of selection, produced a truncated LplA mutant with lipoylation activity equivalent to full-length LplA. We next sought to evolve activity for an unnatural small molecule probe, but found that this strategy was limited by both increased hydrophobic probe sticking when using the truncated enzyme and some enzyme-dependent nonspecificity. Finally, from a library of 107 LplA mutants, we evolved a full-length LplA capable of ligating an unnatural picolyl azide (pAz) substrate. We demonstrated improved activity of the "pAz ligase" in the secretory pathway and cell surface, two regions where coumarin ligase is inactive. This enzyme can also be used to image cell surface protein-protein interactions as well as label proteins as they are trafficked through the endoplasmic reticulum. These probe ligases will be useful tools for cell biologists interested in studying protein function or protein-protein interactions in the context of living cells.