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The Importance Of Proteins

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Proteins are the metabolic workhorses of the cell; they engage in a variety of essential activities ranging from enzymatically catabolizing macromolecular food sources to serving as structural components that maintain cell stability. Maximizing protein function relies on intricate non-covalent interactions occurring on the secondary, tertiary, and quaternary levels that help determine the overall shape of the protein. In their native states, proteins will assume the most energetically favorable configuration. Occasionally however, cells are exposed to exogenous disruptions such as heat stress. Heat Stress can compromise protein three-dimensional structure. Hydrophobic residues tend to be buried in the interior of the protein but when…show more content…
sHSPs are a ubiquitous class of chaperones found across all kingdoms of life. sHSP range in size from 12-42 kilo Daltons in large oligomers of 12 to >32 subunits and the structure is homologous across all species. The sHSP monomer consists of three domains: a disordered N-terminal arm, a beta-sandwich α-crystallin domain, and a flexible C-terminal extension. The N-terminal domain is the most variable region with little conservation between species. Experimental evidence also suggests N-terminal involvement in substrate binding and protection. The α-crystallin domain is the most highly conserved region and adopts a β-sandwich conformation composed of 7 to 8 anti-parallel β-strands (Basha et al, 2012). The C-terminus contains an I-X-I motif, which helps to satblizie the oligomeric form of the sHSP (Basha et al, 2012).
Data from previous studies suggest that the inactive sHSP takes on the oligomer conformation Upon stress, these oligomers assemble into active dimeric species, exposing previously inaccessible hydrophobic surfaces that can then interact with nonpolar patches on the misfolded substrate, capturing them in large complexes. The sHSP-substrate complexes maintain the substrate in a folding-competent state for extended periods of time. Biologically this is of utmost importance since it is
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