Understanding the intricate three-dimensional structure of proteins is fundamental to unraveling biological mechanisms and developing new therapies. Historically, obtaining high-resolution protein structures has been a complex and time-consuming endeavor. While tools exist that can predict protein structure from amino acid sequence, particularly with advancements in computational methods, experimental protein structure determination remains crucial for validating predictions, capturing dynamic states, and achieving the highest resolutions needed for rational drug design and detailed mechanistic studies. ShuimuBio offers a comprehensive, integrated platform designed to streamline the process of protein structure determination, effectively taking researchers from gene sequence to protein high-precision 3D structure through a one-stop solution.
The Critical Need for Experimental Protein Structure Determination
The amino acid sequence of a protein dictates its potential 3D structure, but achieving that structure experimentally requires overcoming significant challenges, particularly for complex targets like membrane proteins. Experimental protein structure determination provides definitive, high-resolution insights into how a protein folds, how it interacts with other molecules (like small molecules, antibodies, or nucleic acids), and how its structure relates to its function. These experimentally determined structures are indispensable for drug discovery, enabling structure-based drug design, understanding drug mechanisms, and guiding optimization.
While computational methods can generate plausible models from amino acid sequences, experimental techniques capture the real-world nuances, conformational changes, and interactions that are vital for many research and development applications. ShuimuBio specializes in these experimental methods, offering a suite of services that cover the entire workflow.
ShuimuBio's Integrated Approach to Protein Structure Determination
ShuimuBio positions itself as Asia's first commercial platform providing cryo-electron microscopy (Cryo-EM) structure determination services, founded in 2017 with a core team of experts in life sciences, computation, IT, and the pharmaceutical industry. Their core advantage lies in their ability to provide a seamless, integrated workflow, taking projects from the initial gene sequence through protein preparation and finally to high-resolution structure determination.
The journey from gene sequence to determined structure involves several critical steps:
1. Protein Preparation and Analysis: Starting with the gene sequence, ShuimuBio's platform handles protein expression using various systems, including E. coli, mammalian cells, insect cells, and cell-free systems, chosen based on the specific protein target. They have significant experience in producing and purifying challenging proteins, such as membrane proteins (GPCRs, ion channels, transporters). Purification processes utilize techniques like affinity chromatography, ion exchange chromatography, gel filtration chromatography, and RP-HPLC. Rigorous quality control methods such as SDS-PAGE, Western blot, mass spectrometry, and thermal stability tests are employed to ensure the purity and homogeneity required for structural studies.
2. Sample Characterization: Before high-resolution data collection, initial characterization is often performed. Negative Staining and Negative Staining 2D services are available to quickly assess protein particle size, homogeneity, shape, and potential aggregation at a lower cost and resolution. This helps optimize samples before proceeding to more resource-intensive steps.
3. Cryo-Sample Preparation: Preparing samples in a native-like, frozen state is crucial for Cryo-EM. ShuimuBio offers expertise in this, including techniques to address challenges like aggregation, preferred orientation, and damage at the air-water interface, utilizing technologies like their self-developed GraFuture™ graphene grids. Cryo-Characterization services are specifically offered for samples like AAV, liposomes, LNPs, and VLPs.
4. High-Resolution Data Collection (Machine Time Service): ShuimuBio boasts a globally scaled commercial Cryo-EM platform with 8 high-end 300kV Cryo-EM microscopes located in Beijing (2 units) and Hangzhou (6 units). They offer 24-hour machine time service, supported by dedicated technical engineers and daily maintenance to ensure optimal equipment performance and high data collection efficiency. Their AI-driven SMART software aids in data analysis efficiency and can reduce machine time.
5. Protein Structure Determination: This is where the high-resolution structure is determined using advanced techniques:
o Single Particle Analysis (SPA): A powerful Cryo-EM technique to resolve the 3D structure of biological macromolecules like proteins and viruses from numerous 2D images. SPA is particularly effective for challenging targets such as Protacs, membrane proteins (GPCRs, ion channels, transporters), VLPs, peptides, and small molecule-target interactions. ShuimuBio highlights their extensive experience with SPA projects.
o MicroED (Microcrystal Electron Diffraction): A cutting-edge technique specifically useful for resolving high-resolution structures from tiny crystals (microcrystals and nanocrystals), applicable to small molecule drugs, peptides, and protein crystals. ShuimuBio has successfully delivered a high percentage of MicroED projects, achieving resolutions as high as 0.6-1.0 Å.
o One-Stop Crystal Structure Determination: Utilizing X-ray crystallography, this service is provided for biological molecules like antigen-antibody complexes, small molecule drugs, and peptides, covering the process from protein preparation and crystallization to data collection and structure解析.
ShuimuBio's team of top scientists, many with Ph.D.s from leading institutions, are specialized in structural biology, protein science, and computational biology, ensuring professional execution and analysis throughout these complex processes. They have accumulated extensive experience, successfully determining structures for over 150 proteins and completing over 400 Cryo-EM and MicroED projects, reaching resolutions as fine as 1.8 Å and even 1.4 Å in some cases.
Applications of Structure Determination
The ability to reliably and efficiently perform protein structure determination has profound impacts across various fields, as demonstrated by ShuimuBio's project experience and published work:
· Vaccine Development: Resolving viral protein structures helps understand invasion mechanisms and guides vaccine design. Cryo-EM has been used for structures of SARS-CoV-2 spike protein complexes, influenza virus proteins, and measles virus neutralization mechanisms. Structure determination also plays a crucial role in vaccine quality control, assessing particle morphology, size, integrity, and aggregation.
· Antibody Drug Discovery: Determining the structure of antibody-antigen complexes reveals recognition mechanisms and binding sites, essential for designing more effective antibody drugs. Cryo-EM facilitates the study of antibody drug mechanisms, optimization, and design, particularly for complex targets like membrane proteins.
· Small Molecule Drug Discovery: Protein structure determination is key to identifying drug targets and understanding drug-target interactions. Resolving structures of targets like GPCRs with small molecule ligands provides the structural basis for designing selective and potent drugs. Structure-based approaches, including fragment-based drug discovery, are significantly accelerated by high-resolution structures obtained through Cryo-EM and MicroED.
ShuimuBio's Advantages for Your Research
Choosing ShuimuBio for your protein structure determination needs means leveraging their core advantages:
· One-Stop Solution: A fully integrated service from gene sequence to final structure, minimizing sample handling and potential issues.
· Global Scale: Operating one of the largest commercial Cryo-EM platforms.
· Extensive Experience: Proven track record with hundreds of projects and published results in top journals.
· Advanced Technology: Utilizing state-of-the-art Cryo-EM facilities, self-developed AI software (SMART, NanoSMART), and GraFuture™ grids to enhance efficiency and resolution.
· High-Resolution Capability: Consistently achieving high-resolution structures, including near-atomic and sub-atomic resolutions with MicroED.
· Expert Team: Access to a highly qualified team of scientists dedicated to solving challenging structural problems.
Navigating the path from a protein's amino acid sequence to its experimentally determined high-resolution 3D structure can be complex. ShuimuBio's one-stop platform simplifies this process, providing the expertise and technology needed for successful protein structure determination.
To learn more about how ShuimuBio can support your protein structure determination projects, from gene sequence to high-resolution structure, please visit https://shuimubio.com/.