On your internship, you visit the Mass Spectrometry Lab. Mass spectrometry can identify short peptide fragments based on their molecular weights. Your fellow intern Jerry has neglected to label his tubes of amyloid beta peptide 42 after digesting them with some proteases that we learned about in Module 6: pepsin, trypsin, and chymotrypsin. Help him figure out what protease is in each tube. Jerry’s supervisor has the fragments listed in the same order as the original peptide primary sequence, which is shown as the three-letter amino acid code, left-to-right from the free amino end (N-terminal) to the carboxyl end (C-terminal). Each fragment is listed as a separate line, in order.
Consider the sequence for the amyloid beta peptide 42, which is involved in Alzheimer’s disease:
Asp-Ala-Glu-Phe-Arg-His-Asp-Ser-Gly-Tyr-Glu-Val-His-His-Gln-Lys-Leu-Val-Phe-Phe-Ala-Glu-Asp-Val-Gly-Ser-Asn-Lys-Gly-Ala-Ile-Ile-Gly-Leu-Met-Val-Gly-Gly-Val-Val-Ile-Ala
Tube A:
Asp-Ala-Glu-Phe
Arg-His-Asp-Ser-Gly-Tyr
Glu-Val-His-His-Gln-Lys-Leu
Val-Phe
Phe
Ala-Glu-Asp-Val-Gly-Ser-Asn-Lys-Gly-Ala-Ile-Ile-Gly-Leu
Met
Val-Gly-Gly-Val-Val-Ile-Ala
Tube B:
Asp-Ala-Glu
Phe-Arg-His-Asp-Ser-Gly
Tyr-Glu-Val-His-His-Gln-Lys-Leu-Val
Phe
Phe-Ala-Glu-Asp-Val-Gly-Ser-Asn-Lys-Gly-Ala-Ile-Ile-Gly-Leu-Met-Val-Gly-Gly-Val-Val-Ile-Ala
Tube C:
Asp-Ala-Glu-Phe-Arg
His-Asp-Ser-Gly-Tyr-Glu-Val-His-His-Gln-Lys
Leu-Val-Phe-Phe-Ala-Glu-Asp-Val-Gly-Ser-Asn-Lys
Gly-Ala-Ile-Ile-Gly-Leu-Met-Val-Gly-Gly-Val-Val-Ile-Ala
On your internship, you visit the Mass Spectrometry Lab. Mass spectrometry can identify short peptide fragments...
How many amino acids are there in the disease causing variant of the Amyloid-beta (Ab) peptide? Determine which of these four peptides is most likely to become a beta sheet. Lys-Thr-Val-Ile-Trp-Pro-Phe-Tyr-Ile-Gln-Ile-Gly Arg-Ser-Tyr-Glu-Gly-Leu-Lys-Arg-Ile-Ala-Glu-Ser Ala-Glu-Met-Leu-Gln-Lys-Arg-Gly-Cys-Gly-Asp-Glu Met-Leu-Lys-Ala-Ser-Ala-Leu-Glu-Lys-Leu-Ser-Glu
5. Consider the following peptide: His-Ser-Gln-Gly-Thr-Phe-Thr-Ser-Asp-Tyr-Ser-Lys-Tyr-Leu-Asp-Ser-Arg-Arg-Ala-Gin- Asp-Phe-Val-Gln-Trp-Leu-Met-Asn-Thr a. What are the fragments, if it is cleaved by trypsin? b. What are the fragments, if it is cleaved by chymotrypsin? c. What are the fragments, if it is cleaved by pepsin?
please explain how to solve this problem, the answer is provided 9. Peptides: (20 pts.). A polypeptide (X) gives 7 fragments when treated with chymotrypsin (A-G). The same peptide also gives 9 fragments when treated with trypsin (I- IX). After Chymotrypsin A) Thr-Thr-Tyr-Ala-Gly-Phe-Phe-Ile-Asp- Lys B) Ala-Cys-Pro-Leu-Tyr-Gin-lle-Arg C) Met-Ser-Thr-Tyr-Pro-Gly-Arg D) Cys-Leu-Val-Phe-Ile-Lys E) Leu-Ala-Trp-Gly-Val F) Ser-Phe-Ala-Pro-Lys G) Met-Asp-Lys Afier Trypsin I) Ala-Pro-Lys-Met-Asp-Lys-Thr-Thr-Tyr II) Pro-Gly-Arg-Cys-Leu-Val-Phe III) Ile-Lys-Ala-Cys-Pro-Leu-Tyr IV) Ile-Asp-Lys-Met-Ser-Thr-Tyr V) Gin-Ile-Arg-Leu-Ala-Trp VIAla-Gly-Phe VII) Gly-Val VIII) Ser-Phe LX) Phe A) What is the primary...
. Insulin (below) is treated with dansyl chloride followed by its complete acidic hydrolysis. Which of the following dansylated amino acids you expect to observe? A chain Gly-Ile-Val-Glu-Gln-Cys-Cys- Ala-Ser-Val - Cys-Ser-Leu- Tyr-Gln-Leu-Glu-Asn - Tyr-Cys- Asn 10 15 21 B chain Phe-Val - Asn-Gln-His-Leu-Cys-Gly-Ser-His-Leu-Val-Glu - Ala-Leu-Tyr-Leu-Val-Cys-Gly-Glu-Arg-Gly-Phe-Phe-Tyr-Thr-Pro-Lys - Ala 10 20 25 30 15
PLEASE HELP OCHEM QUESTION 1. In the following protein, identify the type of bonding or interaction that is responsible for holding the two peptide chains together at each amino acid pair, above (A) and below (B). Gly - Ala - Ser - Cys - Val - Asp - Leu - Thr - His - Ile-Tyr-Glu - Phe - Lys - Cys - Met - Asn Val - Leu -Gin-Cys - Pro-Lys - Met - Tyr - Asp -Phe-Asn-Lys - Ile...
Which of these protein sequences is most likely to span a cell membrane? Gly-Asp-Val-Ala-Gly-Arg-Gly-Asn-Gly-Lys-Lys-Pro-Ser-Ser-Val-Arg-Ala-Leu-Ser Ile-Val-Leu-Pro-Ile-Val-Leu-Leu-Val-Phe-Leu-Cys-Leu-Gly-Val-Phe-Leu-Leu-Trp Lys-Asn-Trp-Arg-Leu-Lys-Asn-Ile-Asn-ser-Ile-Asn-Phe-Asp-Asn-Pro-Val-Tyr-Gln A. 773 B. 792 C. 811
What two restriction enzymes could you use if you wanted to produce a protein that was fused to a GST-tag that could be removed using thrombin? Would this experimental design place any other tags on your protein? Here is the vector: T7 promoter lac operator Xbal rbs Ndel AATTAATACGACTCACTATAGGGGAATTGTGAGCGGATAACAATTCCCCTCTAGAAATAATTTTGTTTAACTTTAAGAAGGAGATATACATATGTCCCCT Met Ser Pro GST Ta His TagSacl ATACTAGGTTAT.627bp...GACCATCCTCCAAAATCGGATGGTTCAACTAGTGGTTCTGGTCATCACCATCACCATCACTCCGCGGGTCTGGTGCCACGCGGTAGT lle Leu Gly Tyr.. .209aa. . . Asp His Pro Pro Lys Ser Asp Gly Ser Thr Ser Gly Ser Gly His His...
The next DNA sequence is the MATRICE strand of a small gene. What is the complete amino acid sequence of the encoded peptide? GTCATGGCAACATAG 5'-3 Standard Genetic Code First position (5'end) U Second position UAU Tyr UAC Tyr UCA Ser UAA StopUGA Stop UAG Stop UUU Phe UUC Phe UUA Leu UUG Leu UGU Cys UGC Cys UCU Ser UCC Ser UCG Ser UGG Trp CUU Leu CUC Leu CUA Leu CUG Leu CCU Pro CCC Pro CCA Pr CCG...
a) Line up the fragments below so that fragments with the same sequences overlap. Drag each fragment to the appropriate location. Gly-Val-Tyr Gly-Val-Tyr-Arg Arg-Asn-Tyr Asn-Tyr-Ala-Val-Thr-Cys-Asn-Gln-Lys Ala-Val-Thr-Cys-Asn-Gln-Lys-Trp Trp-Ser Ser continued below... b) Write the sequence of the peptide. Ala-Arg-Asn-Asp-Cys-Gln-Gly-Lys-Pro-Ser-Thr-Trp-Tys
Met-Ala-Arg-Tyr-Ala-Asn-Asn-Glu__Lys-Glu-Leu-Leu-Tyr__Arg-Tyr-Ala-Asn__Phe-Leu-Ala-Asn-Asn-Ile-Gly-Ala-Asn__Ile-Ser__Ile-Asn-Thr-Glu-Arg-Glu-Ser-Thr-Glu-Asp__Ile-Asn__ His-Glu-Arg__Phe-Ala-Thr-His-Glu-Arg-Ser__Thr-Arg-Ile-Gly-Leu-Tyr-Cys-Glu-Arg-Ile-Asp-Glu__Leu-Glu-Val-Glu-Leu-Ser__Ser-Ile-Asn-Cys-Glu__His-Glu-__His-Ala-Pro-Pro-Ile-Leu-Tyr__Glu-Ala-Thr-Ser__Val-Ala-Asn-Ile-Leu-Leu-Ala__Cys-Ala-Lys-Glu-__Ala-Asn-Asp__Pro-Glu-Cys-Ala-Asn__Pro-Ile-Glu__Trp-Ile-Thr-His__Phe-Arg-Ile-Glu-Asp__Cys-His-Glu-Glu-Ser-Glu-Cys-Ala-Lys-Glu__Ile-Cys-Glu__Cys-Arg-Glu-Ala-Met__Glu-Val-Glu-Arg-Tyr-Asp-Ala-Tyr__Ala-Asn-Asp__Ser-His-Glu__Ile-Ser__Asp-Glu-Val-Ala-Ser-Thr-Ala-Thr-Glu-Asp__Thr-His-Ala-Thr__Asp-Ile-Ser-Glu-Ala-Ser-Glu-Ser__Leu-Ile-Lys-Glu__His-Glu-Ala-Arg-Thr__Asp-Ile-Ser-Glu-Ala-Ser-Glu__Ser-Leu-Glu-Glu-Pro__Ala-Pro-Asn-Glu-Ala__Ser-Glu-Val-Glu-Arg-Glu__Trp-Glu-Ile-Gly-His-Thr__Gly-Ala-Ile-Asn__Trp-Ile-Leu-Leu__Ala-Arg-Ile-Ser-Glu__Ile-Phe__His-Glu__Lys-Glu-Glu-Pro-Ser__Thr-His-Ile-Ser__Glu-Ala-Thr-Ile-Asn-Gly__Pro-Ala-Thr-Thr-Glu-Arg-Asn__Tyr-Glu-Thr__Ile-Phe__His-Glu__Trp-Trp-Trp-Trp-Ile-Ile-Ile-Ile-Ile-Leu-Leu-Leu-Leu-Leu-Ser-Ser-Ser-Ser__Cys-His-Ala-Asn-Gly-Glu__Ile-Asn__His-Ile-Ser__Leu-Ile-Phe-Glu-Ser-Thr-Tyr-Leu-Glu__His-Glu__Cys-Ala-Asn__Ser-Thr-Ile-Leu-Leu__Arg-Glu-Met-Ala-Ile-Asn__His-Glu-Ala-Leu-Thr-His-Tyr__Ser-Ala-Ser-Ser-Tyr__Ala-Asn-Asp__Ala-Leu-Arg-IleGly-His-Thr 1.) Write out the 1 letter amino acid abbreviation for each of the three-letter amino acid abbreviated words listed in the given sequence. The __ indicates a space in between the words. Use www.expasy.org and other bioinformatic tools to generate the following bioinformatic data for the given polypeptide sequence. You must give the name and link to the program you used to generate the data: 2.) Compute the pI and Mw (isoelectric point and molecular mass, respectively) of...