1Department of Biochemistry and Molecular Biology, SUNY Upstate Medical University
The protocols here describe kinetic assays of protein-protein interactions with Bio-layer Interferometry. F-type ATP synthase, which is involved in cellular energy metabolism, can be inhibited by its ε subunit in bacteria. We have adapted Bio-layer Interferometry to study interactions of the catalytic complex with ε’s inhibitory C-terminal domain.
Published February 18, 2014. Keywords: Chemistry, ATP synthase, Bio-Layer Interferometry, Ligand-induced conformational change, Biomolecular Interaction Analysis, Allosteric regulation, Enzyme inhibition
1School of Life Sciences, University of Nottingham
Kinesins are characterized by nucleotide-dependent interaction with microtubules: a cycle of ATP turnover coupled to a cycle of microtubule interaction. Here, we describe protocols to analyze the kinetics of individual nucleotide transitions in the ATP turnover cycle of a kinesin using fluorescently labeled nucleotides and stopped-flow fluorescence.
Published October 17, 2014. Keywords: Chemistry, Kinesin, ATP turnover, mantATP, mantADP, stopped-flow fluorescence, microtubules, enzyme kinetics, nucleotide
JoVE Immunology and Infection
1Department of Veterinary Pathobiology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, 2Department of Microbial and Molecular Pathogenesis, College of Medicine, Texas A&M University System Health Science Center, 3University of California, Irvine, 4Department of Medical Microbiology & Immunology, School of Medicine, University of California, Davis
A high-throughput assay to in vitro phenotype Salmonella or other bacterial association, invasion, and replication in phagocytic cells with high-throughput capacity was developed. The method was employed to evaluate Salmonella gene knockout mutant strains for their involvements in host-pathogen interactions.
Published August 11, 2014. Keywords: Infectious Diseases, Salmonella enterica Typhimurium, association, invasion, replication, phenotype, intracellular pathogens, macrophages
1Department of Pathology, New York University School of Medicine, 2New York University Center for Health Informatics and Bioinformatics, 3NYU Cancer Institute, 4Department of Pathology and Yale Cancer Center, Yale University School of Medicine
Here we describe a protocol for simultaneous detection of histone modifications by immunofluorescence and DNA sequences by DNA FISH followed by 3D microscopy and analyses (3D immuno-DNA FISH).
Published February 3, 2013. Keywords: Genetics, Molecular Biology, Bioinformatics, Cancer Biology, Pathology, Biomedical Engineering, Immunology, Intranuclear Space, Nuclear Matrix, Fluorescence in situ Hybridization, FISH, 3D DNA FISH, DNA, immunofluorescence, immuno-FISH, 3D microscopy, Nuclear organization, interphase nuclei, chromatin modifications
1Department of Biology, Technion - Israel Institute of Technology
Many mRNAs encoding mitochondrial proteins are associated with the mitochondria outer membrane. We describe a subcellular fractionation procedure aimed at isolation of yeast mitochondria with its associated mRNAs and ribosomes. This protocol can be applied to cells grown under diverse conditions in order to reveal mechanisms of mRNA localization and localized translation near the mitochondria.
Published March 14, 2014. Keywords: Biochemistry, mitochondria, mRNA localization, Yeast, S. cerevisiae, microarray, localized translation, biochemical fractionation
1School of Life Sciences, Arizona State University
The Proboscis Extension Response (PER) conditioning protocol, developed for the honey bee (Apis mellifera), provides an ecologically-relevant and easily quantifiable means for studying several different mechanisms of learning in many insect species.
Published September 8, 2014. Keywords: Neuroscience, PER, conditioning, honey bee, olfaction, olfactory processing, learning, memory, toxin assay
1Brain and Cognition, University of Amsterdam
Reading in color is a new method for training letter-color associations that are typically found only in grapheme-color synesthetes. It involves an implicit form of training that has potential for long-term associative training methods because the training is a byproduct of reading and any text can be colored.
Published February 20, 2014. Keywords: Behavior, synesthesia, training, learning, reading, vision, memory, cognition
1Division of Human Genetics, Children's Hospital of Philadelphia Research Institute, 2Department of Pediatrics, Perelman School of Medicine, University of Pennsylvania
The combination of chromatin immunoprecipitation and ultra-high-throughput sequencing (ChIP-seq) can identify and map protein-DNA interactions in a given tissue or cell line. Outlined is how to generate a high quality ChIP template for subsequent sequencing, using experience with the transcription factor TCF7L2 as an example.
Published April 19, 2013. Keywords: Molecular Biology, Genetics, Biochemistry, Microbiology, Medicine, Proteins, DNA-Binding Proteins, Transcription Factors, Chromatin Immunoprecipitation, Genes, chromatin, immunoprecipitation, ChIP, DNA, PCR, sequencing, antibody, cross-link, cell culture, assay
1Department of Bacteriology, University of Wisconsin-Madison
To study the mutualism between Xenorhabdus bacteria and Steinernema nematodes, methods were developed to monitor bacterial presence and location within nematodes. The experimental approach, which can be applied to other systems, entails engineering bacteria to express the green fluorescent protein and visualizing, using fluorescence microscopy bacteria within the transparent nematode.
Published October 19, 2012. Keywords: Microbiology, Molecular Biology, Bacteriology, Developmental Biology, Colonization, Xenorhabdus, Steinernema, symbiosis, nematode, bacteria, fluorescence microscopy
1GE Healthcare Bio-Sciences AB
We apply label-free protein interaction analysis using Biacore X100 for structure-function analysis of the binding of several cystatin B mutants to papain through kinetic characterization. Calibration-free concentration analysis (CFCA) measures the concentration of protein with retained binding activity without the need for a standard curve. We show that confirmation of concentrations using CFCA increases the reliability of the kinetic analysis and that kinetic constants can reliably be determined even if the activity of a recombinant protein is reduced.
Published March 17, 2010. Keywords: Cellular Biology, Protein interaction, Surface Plasmon Resonance, Biacore X100, CFCA, Cystatin B, Papain