Heat shock proteins characteristics

Only recently have heat shock proteins been used in the stabilization of nanoparticles. Aida et al. have demonstrated the inclusion of already preformed CdS nanoparticles within the chaperonin proteins of GroEL from Escherichia coli and T.th cpn from Thermus thermophilus HB8. These proteins were chosen as a result of sharing similar structural characteristics (1) tubular structure measuring 14.6nm in length, (2) cylindrical cavity with a 4.5-nm diameter, and (3) stability to adverse conditions (pH and temperature). T.th cpn, however, contains an additional bowl-shaped capping protein. 

From this, in Forterre s thermoreduction hypothesis (1995), came several lines of descendants. Some became colonists of much hotter environments. Of these lines, some necessarily streamlined both their genomes and their physiology, in order to survive, while others, also with reduced physiology, developed heat shock proteins to correct damage. This led to the distinct domains, the Bacteria and Archea. In contrast, other descendants retained the complex more primitive physiology— biplanes or triplanes, as opposed to prokaryote monoplanes. This third line became the Eucarya. This third line may share some characteristics with the planctomycetes (Fuerst, 1995 Lindsay et al, 2001). 

The temperature increase induces the synthesis of a new o factor, which directs RNA polymerase to promoters that have -10 and -35 sequences which are different from those recognized by Transcription from these promoters gives rise to characteristic heat-shock proteins. 

The protein expression patterns obtained by 2-DE in B cell chronic lymphocytic leukaemia was also studied by T. Voss and collaborators in 24 patient samples (Voss et al, 2001). This analysis allowed the identification of proteins that clearly discriminated between different patient groups (with defined chromosomal characteristics or according to clinical parameters). More particularly, this study showed that B cell chronic lymphocytic leukaemia patients with shorter survival exhibit changed levels of redox enzymes such as heat shock protein 27 and protein disulfide isomerase. 

Hatayama T, Tsukimi Y, Wakatsuki T, et al. 1992. Characteristic induction of 70000-DA-heat shock protein and metallothionein by zinc in HELA-cells. Mol Cell Biochem 112(2) 143-153. 

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