IgA1 (immunoglobulin A1) functions as an immune molecule, against microbial invaders and other pathogens, on the surface of animal and human cells, especially on the mucosal membrane. To impair the function of immunoglobulin the human immune system some bacteria secrete site-specific IgA1 proteases to cleave IgA1 at hinge region. The protease has therefore been implicated as a putative virulence factor. Although the alignment of the DNA for the proteases predicted the IgA1 protease domain and catalytic site, lack of experimental evidence hindered in both structural and functional enzymic studies. In order to elucidate and understand the exact activity, this study aims at to analyze catalytic site of IgA1 protease from H. influenza, and thus PCR was used to amplify the DNA for putative reactive site domain (1-885) and protease domain (1-2373), respectively, were cloned in pGEM-T and transferred to the expression vector, pTrcHis-A for production of the recombinant proteins. Analysis of the recombinant proteins shows that the Human IgA1 heavy chain hydrolyzed by the protease domain recombinant protein but putative reactive site. This demonstrates that protease domain is enough for protease activity. The putative reactive site domain alone is incapable in hydrolyzing Human IgA1.

The following thesis project has been done in direct collaboration with Autokaross i Floby AB Rescue Vehicle Department, in Sweden.  The report contains the design development of a protective cover against weather conditions for the extendable ladder in a fire vehicle.   The aim of the report has been to develop a functional and low cost solution cover for the FEL on a fire truck, which is allocated on the roof, with the express intention of providing adequate access and protection against weather conditions in Nordic countries, so as to prevent premature deterioration of the FEL unit. The company has set the technical and conceptual boundaries, with the help of the two previous concepts currently used, the BMC and the ACP.   The initial requirements laid out by the company were expressed through a number of specific demands which can be categorized in two main points:   Cost: Designing a solution keeping in mind cost limits, assembly cost and time, and space optimization. This was done by taking into account the two existing solutions, particularly the BMC, which represents the lowest, cost wise and function wise. Therefore it was used as the basis on which to apply improvements, rather than trying to lower the high cost on the overqualified function of the ACP.   Function: Providing the adequate protection and access to the FEL. In this case, the problem was solved by establishing the correct degree of protection relevant to the Nordic weather conditions and FEL needs, and regarding the access, this was assured by fully automating the opening/closing process with the existing extraction operating system of the FEL.     The result of this report is a concept solution which meets the company’s demands, obtained by creative detailing, together with an analysis regarding possible considerations that could improve the creative detailing result in this report in the form of future work.     The report documents the process that has taken place in exploration, concept generation, concept evaluation, concept selection, and detailed CAD development. Each section shows the requirements and adjustments taken to fulfil the company’s needs.