Harper’s Illustrated Biochemistry 30th Edition PDF Free Download
The authors and publishers are pleased to present the thirtieth edition of Harper’s Illustrated Biochemistry. The first edition, entitled Harper’s Biochemistry, was published in 1939 under the sole authorship of Dr Harold Harper at the University of California School of Medicine, San Francisco, California. Presently entitled Harpers Illustrated Biochemistry, the book continues, as originally intended, to provide a concise survey of aspects of biochemistry most relevant to the study of medicine. Various authors have contributed to subsequent editions of this medically oriented biochemistry text, which is now observing its 75th year. Cover Illustration for the Thirtieth Edition The illustration on the cover depicts the proteasome and the initial proteolytic degradation of an ubiquitinated intracellular protein. The proteosome consists of a macromolecular complex of 14 α and 14 b subunits (shown green and yellow, respectively) arranged as four stacked α7b7b7a7 rings.
These form a hollow, tube-like chamber that contains immobilized proteases. A polypeptide tagged for degradation (shown red) enters the proteasome (top left) and is hydrolyzed into peptide fragments by internal proteases of the proteosome. Following their exit from the proteosome (bottom, right), extracellular proteases degrade these peptide fragments to amino acids. The timely and controlled degradation of intracellular proteins is critical to such fundamental biological processes as cell differentiation and division. The ability to recognize and dispose of denatured or damaged proteins is essential to health, since the accumulation of protein aggregates contributes significantly to the etiology of a variety of human diseases, including numerous neurological disorders. For the discovery of ubiquitin-mediated protein degradation, Aaron Ciechanover and Avram Hershko of Israel and Irwin Rose of the United States were awarded the 2004 Nobel Prize in Chemistry.