Rickettsia rickettsii is a bacterium that is primarily transmitted to humans through the bite of infected ticks, resulting in a severe illness known as Rocky Mountain spotted fever. This bacterium has several surface proteins, including a surface protein antigen and an outer membrane protein B (cell surface antigen sca5), which play a crucial role in its pathogenesis.

The surface protein antigen of Rickettsia rickettsii is an important component of the bacterium’s outer membrane. It is believed to be involved in the attachment and invasion of host cells, as well as the evasion of host immune responses. This protein is highly immunogenic and has been used in diagnostic tests for Rocky Mountain spotted fever.

The outer membrane protein B of Rickettsia rickettsii, also known as cell surface antigen sca5, is another important surface protein. It is involved in the adhesion of the bacterium to host cells and has been shown to play a role in the pathogenesis of Rocky Mountain spotted fever. This protein is also highly immunogenic and has been used in diagnostic tests.

In recent years, there has been an increased interest in the application of cDNA and recombinant antigens for the diagnosis of RMSF. cDNA-based approaches can be used to detect the presence of Rickettsia rickettsii in a clinical sample using PCR-based assays, while recombinant antigens can be used to detect specific antibodies in the serum of patients. cDNA-based assays have been found to be more sensitive and specific than traditional diagnostic methods, such as serology and culture. Recombinant antigens offer the advantage of being able to detect a broader range of RMSF-specific antibodies than traditional serological assays. Both cDNA-based and recombinant antigen-based assays have been used successfully in clinical settings to diagnose RMSF. The use of cDNA and recombinant antigens for the diagnosis of RMSF is an important step forward in improving the diagnosis and treatment of this disease.

The use of recombinant proteins/cDNA in academic research and therapeutic applications has skyrocketed. However, in heterologous expression systems, successful recombinant protein expression is dependent on a variety of factors, including codon preference, RNA secondary structure, and GC content. When compared to pre-optimization, more and more experimental results demonstrated that the expression level was dramatically increased, ranging from two to hundred times depending on the gene. Bioclone has created a proprietary technology platform that has resulted in the creation of over 6,000 artificially synthesized codon-optimized cDNA clones (cloned in E. coli expression Vector), which are ready for production of the recombinant proteins.