Rickettsia africae cDNA and Antigen

Rickettsia africae is a gram-negative bacterium that belongs to the spotted fever group (SFG) of the genus Rickettsia. This bacterium is primarily transmitted to humans through the bite of infected ticks, particularly Amblyomma species. The disease caused by R. africae is called African tick-bite fever, and it is endemic in several African countries, including South Africa, Zimbabwe, and Kenya.

R. africae expresses several cell surface antigens, which are proteins that are exposed on the outer surface of the bacterium and are recognized by the host immune system. These antigens play a crucial role in mediating the interaction between R. africae and its host, including adhesion to host cells, invasion, and evasion of the host immune system. Four of the most studied R. africae cell surface antigens are Sca2, Sca12, Sca9, and Sca2.

Sca2 is a 120 kDa protein that belongs to the autotransporter protein family. Autotransporters are bacterial virulence factors that are involved in a variety of functions, including adhesion, biofilm formation, and secretion of toxins. Sca2 has been shown to be involved in adhesion to host cells, particularly endothelial cells, and it is essential for R. africae invasion. Sca2 has also been shown to elicit a strong antibody response in infected individuals, making it a potential target for diagnostic tests and vaccines.

Sca12 is a 46 kDa protein that belongs to the surface cell antigen (sca) family. Sca12 is expressed on the surface of R. africae and is involved in adhesion to host cells, particularly erythrocytes. Sca12 has also been shown to elicit an antibody response in infected individuals, making it a potential target for diagnostic tests and vaccines.

Sca9 is a 120 kDa protein that is also a member of the autotransporter protein family. Sca9 has been shown to be involved in the invasion of R. africae into host cells, particularly endothelial cells. Sca9 has also been shown to be highly immunogenic, making it a potential target for diagnostic tests and vaccines.

Sca2 is a 160 kDa protein that is a paralog of Sca2. Like Sca2, Sca2 is involved in adhesion to host cells, particularly endothelial cells. Sca2 has also been shown to elicit a strong antibody response in infected individuals, making it a potential target for diagnostic tests and vaccines.

R. africae cell surface antigens, including Sca2, Sca12, Sca9, and Sca2, are important virulence factors that play a crucial role in the pathogenesis of African tick-bite fever. These antigens are potential targets for developing diagnostic tools and vaccines, which could aid in the early detection and prevention of this serious 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.

Rickettsia africae cDNA and recombinant antigen can be used in a wide range of applications in the field of biotechnology. In particular, the cDNA and recombinant antigen can be used in the development of diagnostic tests and vaccines for diseases caused by R. africae. In addition, the cDNA and recombinant antigen can also be used to study the molecular mechanisms of pathogenesis and virulence of Rickettsia species. Furthermore, they can be used to study the genetic diversity of R. africae and to develop new therapies for the treatment of infected individuals.