Tài liệu, ebook Sinh Học

Sickle cell anemia – E6 to V6 Causes V6 to bind to hydrophobic pocket in deoxy-Hb Polymerizes to form long filaments Cause sickling of cells Sickle cell trait offers advantage against malaria Fragile sickle cells can not support parasite

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Stabilize native structure Formed after native conformation achieved Abundant in secreted proteins but not in intracellular proteins Protein disulfide isomerase catalyzes reduction of incorrect disulfide linkages

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Loops Loops usually contain hydrophillic residues. Found on surfaces of proteins Connect alpha-helices and beta-sheets Turns Loops with < 5 AA’s are called turns Beta-turns are common

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Trypsin Met-Ala-Arg Phe-Ala-Glu-Gln-Asp Gly-Glu-Tyr-Met-Cys-Lys Chymotrysin Met-Ala-Arg- Gly-Glu-Tyr Met-Cys-Lys –Phe Ala-Glu-Gln-Asp CNBr Met Ala-Arg-Gly-Glu-Tyr-Met Cys-Lys-Phe-Ala-Glu-Gln-Asp

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Draw the decapeptide at pH 1, 7, and 12. (pay attention to the form the N- and C- terminal and each R-group takes on at each pH) Calculate the overall charge at each pH. Write out the one letter code for the decapeptide

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Buffers are aqueous systems that resist changes in pH when small amounts of a strong acid or base are added. A buffered system consist of a weak acid and its conjugate base. The most effective buffering occurs at the region of minimum slope on a titration curve (i.e. around the pKa). Buffers are effective at pHs that are within +/-1 pH unit of...

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The National Center for Biological Information (NCBI) website contains a vast store of biological information, including genomic and proteomic data Start with a sequence and discover gene to which it belongs, then compare that sequence with that of similar genes Query the database with a topic for information View structures of protein in 3D by...

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Group II introns Retrohome to intronless copies same gene by: Insertion of an RNA intron into the gene Followed by reverse transcription Then second-strand synthesis Retrotranspose by: Insertion of an RNA intron into an unrelated gene Target-primed reverse transcription Lagging-strand DNA fragments as primers Group II retrotransposition...

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When 2 similar, non-identical DNA sequences interact, possibility exists for gene conversion Conversion of one DNA sequence into that of another Sequences participating in gene conversions can be: Alleles, as in meiosis Nonallelic genes, such as the MAT genes that determine mating type in yeast

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Mammalian telomeres form looped structures that protect ss telomeric DNA Proteins TRF1 and TRF2 appear to help telomeric DNA in mammalian cells form a t loop in which ss 3’-end of telomere invades the ds telomeric DNA upstream TRF1 may help bend the DNA into shape for strand invasion TRF2 binds at point of strand invasion, may stabilize the disp...

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