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Question: 12 below is a portion of the abstract of a...

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12. Below is a portion of the abstract of a journal article. It describes the isolation, purification, and determination of the peptide sequence as well as, the location of each of the disulfide bridges of an antibacterial peptide from the cowpea plant. Give brief and to the point answers to the questions based upon this information. (2 pts) FEBS Joumal 273 (2006) 3489-3497 2006 The Authors Journal compilation2006 FEBS Identification of a cowpea y-thionin with bactericidal activity Octávio L. Franco, Andre M. Murad, José R. Leite?,Paulo A M. Mendes, Maura V. Prates and Carlos Bloch Jr Laboratorio de Espectrometria de Massa Embrape Recursos Geneticos e Botecnologie Brsla FB Antimicrobial peptides are an abundant group of proteinaceous com- pounds widely produced in the plant kingdom. Among them, the y-thionin family, also known as plant defensins, represents one typical family and comprises low molecular mass cysteine-rich proteins, usually cationic and distributed in different plant tissues. Here, we report the purification and characterization of a novel γ-thionin from cowpea seeds (Vigna angu- culata), named Cp-thionin II, with bactericidal activity against Gram- positive and Gram-negative bacteria. Once the primary structure was Below is a figure from the article which gives the amino acid sequence for the isolated peptide. CpThioninTCMTKKEGW-GRCLIDTTCAHSCRKYGYMGGKCQGITRRCYCLLNC The black lines above the sequence indicate the disulfide bonds in the structure. You may ignore the dashes.

a. What is the N-terminal residue (three letter code)? b. What is the C-terminal residue (three letter code)? c. How many strongly basic amino acid (R group pKa> 9 and picks up a proton when added to water) residues are present in the sequence? d. How many acidic amino acid (R group pKa < 5) residues are present in the sequence? would you prodot that the pl for this protein would be peater or les tan Briefly justify yar do f. Draw the structure ofresidue number 10 showing the absolute stereo-chemical configuration of the L family of amino acids. g. How many residues in the sequence have hydrocarbon R groups (contain only H and C atoms). Identify these by their one and three letter codes. h. How many residues contain sulfur and how many disul fide bridges are present in the peptide? Residues that contain sulfur Disulfide bridges -

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