| 纯度 | >90%SDS-PAGE. |
| 种属 | Human |
| 靶点 | SPA |
| Uniprot No | Q8IWL2 |
| 内毒素 | < 0.01EU/μg |
| 表达宿主 | E.coli |
| 表达区间 | 21-248aa |
| 氨基酸序列 | EVKDVCVGSPGIPGTPGSHGLPGRDGRDGLKGDPGPPGPMGPPGEMPCPPGNDGLPGAPGIPGECGEKGEPGERGPPGLPAHLDEELQATLHDFRHQILQTRGALSLQGSIMTVGEKVFSSNGQSITFDAIQEACARAGGRIAVPRNPEENEAIASFVKKYNTYAYVGLTEGPSPGDFRYSDGTPVNYTNWYRGEPAGRGKEQCVEMYTDGQWNDRNCLYSRLTICEF |
| 预测分子量 | 26.2 kDa |
| 蛋白标签 | His tag N-Terminus |
| 缓冲液 | PBS, pH7.4, containing 0.01% SKL, 1mM DTT, 5% Trehalose and Proclin300. |
| 稳定性 & 储存条件 | Lyophilized protein should be stored at ≤ -20°C, stable for one year after receipt. Reconstituted protein solution can be stored at 2-8°C for 2-7 days. Aliquots of reconstituted samples are stable at ≤ -20°C for 3 months. |
| 复溶 | Always centrifuge tubes before opening.Do not mix by vortex or pipetting. It is not recommended to reconstitute to a concentration less than 100μg/ml. Dissolve the lyophilized protein in distilled water. Please aliquot the reconstituted solution to minimize freeze-thaw cycles. |
以下是关于SPA(葡萄球菌蛋白A)重组蛋白的参考文献示例(内容为模拟生成，建议通过学术数据库核实)：
1. **《Efficient purification of antibodies using recombinant Protein A fused to cellulose-binding domain》**
- 作者：Smith J, et al.
- 摘要：研究通过将重组SPA与纤维素结合结构域融合，开发了一种新型抗体纯化方法，利用大肠杆菌表达系统实现高产量，显著降低了传统纯化成本。
2. **《Engineering recombinant Protein A for enhanced IgG detection in diagnostic assays》**
- 作者：Li X, Wang Y.
- 摘要：通过基因改造优化重组SPA的Fc结合域，提高了其在ELISA检测中的灵敏度和稳定性，为临床诊断提供了更可靠的工具。
3. **《Structural and functional analysis of a truncated recombinant Protein A variant》**
- 作者：Garcia R, et al.
- 摘要：解析了一种截短型重组SPA的晶体结构，证明其保留完整IgG结合能力的同时，减少了免疫原性，适用于体内治疗性抗体的导向应用。
4. **《Recombinant Protein A-based nanoparticles for targeted drug delivery》**
- 作者：Chen L, et al.
- 摘要：利用重组SPA与肿瘤特异性抗体偶联，构建了靶向药物递送系统，在体外实验中展示了高效的癌细胞选择性杀伤效果。
**建议**：通过PubMed、Web of Science或Google Scholar搜索关键词“recombinant Protein A”+“antibody purification/diagnostic/therapy”获取最新文献。部分经典研究可参考《Journal of Chromatography B》或《Biotechnology Advances》等期刊。
**Background of Recombinant Staphylococcal Protein A (SPA)**
Staphylococcal Protein A (SPA), a cell wall-associated protein derived from *Staphylococcus aureus*, is renowned for its immunoglobulin-binding properties. Discovered in the 1960s, SPA initially gained attention for its ability to bind the Fc region of IgG antibodies, enabling non-immune interactions with mammalian immunoglobulins. This unique feature underpins its widespread use in immunology and biotechnology, particularly in antibody purification, immunoprecipitation, and diagnostic assays.
The advent of recombinant DNA technology revolutionized SPA production. Recombinant SPA is engineered by cloning the *spa* gene into expression vectors (e.g., *E. coli* or mammalian systems), allowing scalable, high-purity production. Unlike native SPA, recombinant variants can be structurally optimized to enhance stability, reduce nonspecific binding, or tailor binding affinity across species (e.g., human, mouse, rabbit IgG). Common modifications include truncating nonessential domains or introducing point mutations to improve pH tolerance during affinity chromatography.
Recombinant SPA is integral to affinity purification resins, where its Fc-binding domain captures antibodies with high specificity, streamlining therapeutic monoclonal antibody (mAb) manufacturing. It also serves as a detection reagent in ELISA and flow cytometry, leveraging its dual binding capacity for IgG and conjugated labels (e.g., fluorescent dyes, enzymes). Beyond research, SPA-derived peptides are explored for therapeutic applications, such as immune modulation by targeting B-cell receptors or inhibiting inflammatory pathways.
Despite its utility, challenges like ligand leakage during purification or cross-reactivity with IgM/IgA in some formats persist. Advances in protein engineering, such as Fc-mutant SPA or hybrid ligands (e.g., combining SPA with Protein G domains), continue to address these limitations, expanding its versatility. Today, recombinant SPA remains a cornerstone in biologics development, diagnostics, and biomedical research, reflecting its enduring relevance in bridging microbial biochemistry with modern biotechnological innovation.
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