Protein Analysis FAQ

• • What Are the Methods for Detecting Histone Modifications

  Histone modifications are biological processes that regulate chromatin structure and function, and are closely associated with key biological events such as gene expression, DNA damage repair, and cell division. Major types of histone modifications include acetylation, methylation, phosphorylation, and ubiquitination. Investigating histone modifications provides critical insights into these fundamental processes. Below are some commonly used methods for detecting histone modifications: 1. Immunoblotting....

• • What Software Can Be Used for Differential Expression Analysis of Proteins in Mass Spectrometry-Based Proteomics

  A wide range of software tools are available for the differential expression analysis of proteins in mass spectrometry-based proteomics. These tools are commonly applied in the preprocessing of mass spectrometry data, feature detection, protein identification, and statistical analysis of differential expression. Commonly used software includes: 1. MaxQuant MaxQuant is a widely adopted platform for the quantitative and differential analysis of high-resolution mass spectrometry data. It supports both ........

• • Where to Find the Amino Acid Sequence of SUMO

  "SUMO" (Small Ubiquitin-like Modifier) refers to a family of proteins that covalently attach to target proteins, thereby modulating their stability, subcellular localization, or biological function. SUMOylation represents a critical form of post-translational modification. The amino acid sequence of SUMO can be obtained through the following commonly used online bioinformatics databases: 1. UniProt (Universal Protein Resource) UniProt is a comprehensive and widely utilized resource for protein sequences....

• • How to Determine Which Protein Exhibits the Most Significant Difference

  In differential proteomic analysis, determining which protein exhibits the most significant expression change typically involves a combination of statistical analysis and bioinformatics approaches. The general procedure includes the following steps: 1. Protein Quantification The first step is to quantify the proteins present in the samples. This is commonly achieved using techniques such as mass spectrometry (MS), protein microarrays, or other quantitative platforms. 2. Statistical Analysis The quantified..

• • How Does Mass Spectrometry Accomplish Peptide Sequence Identification

  The Principle and Process of Peptide Sequence Identification by Mass Spectrometry 1. Sample Preparation and Pre-treatment Protein samples are initially subjected to enzymatic digestion to yield a collection of peptides. These peptides are subsequently purified and enriched to ensure compatibility with downstream mass spectrometric analysis. 2. Ionization Process Prior to mass analysis, peptides are ionized using techniques such as Electrospray Ionization (ESI) or Matrix-Assisted Laser Desorption/Ionization

• • Does Trichloroacetic Acid Method Significantly Affect Polysaccharide Structure

  Trichloroacetic acid (TCA) is a widely employed reagent for protein precipitation, commonly used to isolate and concentrate proteins from biological samples. While this method is effective in precipitating proteins, it may also exert an influence on the structural integrity of polysaccharides. As a strong acid, trichloroacetic acid has the potential to disrupt acid-labile bonds within polysaccharide structures, such as ester linkages and glycosidic bonds. Moreover, the significant pH reduction induced by...

• • How to Interpret Metabolomic Profiles from High-Performance Liquid Chromatography Analysis

  High-performance liquid chromatography (HPLC) is a widely applied technique in metabolomics for the separation and detection of complex metabolite mixtures present in biological samples. The resulting metabolomic profiles provide detailed information on the retention times and relative abundances of individual metabolites. To properly interpret and analyze these profiles, the following key aspects should be considered: 1. X-axis The X-axis represents the retention time (RT), which denotes the time .........

• • What Instruments Are Used for the Qualitative and Quantitative Analysis of Organic-Inorganic Mixtures

  For the qualitative and quantitative analysis of organic-inorganic mixtures, a range of analytical instruments and techniques is available. The following are commonly employed methods: 1. Liquid Chromatography–Mass Spectrometry (LC-MS) LC-MS is widely used for the analysis of organic compounds, offering efficient separation and high detection sensitivity. It enables both qualitative and quantitative analysis of organic components. 2. Inductively Coupled Plasma Mass Spectrometry (ICP-MS) ICP-MS is ..........

• • Is Derivatization Necessary for Amino Acid Analysis Using High Performance Liquid Chromatography

  High performance liquid chromatography (HPLC) is widely employed for the analysis of amino acids; however, derivatization is not always essential. Derivatization is typically applied to enhance specific analytical attributes, such as increasing detection sensitivity, improving chromatographic resolution, or minimizing undesired chemical reactions involving certain amino acids during the analytical process. The following are several common HPLC-based strategies for amino acid analysis:

• • What Are the Functions of Histone Modifications

  Histone modifications play a critical role in regulating gene expression as well as influencing the structural and functional organization of DNA within chromatin. These modifications commonly include acetylation, methylation, phosphorylation, and ubiquitination. They can alter the charge properties of histones, thereby affecting their interaction with DNA and the binding affinity of various non-coding proteins to histones. 1. Acetylation typically occurs on lysine residues of histone proteins. This .......