What is the significance of the secretion “signal peptide” (or secretion signal sequence)? What is it a signal for?
What is the significance of the secretion “signal peptide” (or secretion signal sequence)? What is it...
6. A peptide has the sequence Cys-His-Phe-Glu-Ala-Arg a. Write the single letter sequence of the peptide b. Calculate the percentage and indicate the charge of the predominant peptide species at pH 6.5. Use the following pKa values: pKa Cys = 8.3, pKa N-terminus = 10.8, pKa His =6.0, pKa Glu = 4.3, pKa Arg = 12.5, pKa C-terminus =2.0 c. What is the charge of the peptide at pH 4.3? d. Draw the chemical structure of the predominant peptide species...
You have a peptide whose sequence is secretly known, that you want to analyze. The peptide sequence is D-M-K-T-L-A-R-S-M-E-I-D-Q You have three reagents that cleave polypeptides, CNBr, chymotrypsin, and trypsin into smaller peptides. If you could purify these peptides and sequence them by Edman, but only get four amino acids. 1) what end of the protein does the Edman reaction cleave residues from? n-terminus or c-terminus 2) what are all the Edman sequences (up to 4 amino acids) of the...
What is the net charge of the molecule with peptide sequence “AWRSME” at a pH of 7.4?
The following sequence is part of the DNA TEMPLATE for a 4 amino acid peptide that starts with Methionine. 5- TTATTCTTTAAT CAT-3 What would be the consequences of the highlighted A to be mutated to a G? Select one: a. The resulting peptide will likely be larger than the non-mutant peptide b. the primary sequence of the peptide will be different on one amino acid O C. The peptide sequence would be the same d. all the amino acids after...
The following sequence is part of the DNA TEMPLATE for a 4 amino acid peptide that starts with Methionine. 5'- TTATTCTTTAAT CAT-3' What would be the consequences of the highlighted A to be mutated to a G? Select one: a. the primary sequence of the peptide will be different on one amino acid b. all the amino acids after the mutation will be different than the non-mutant peptide c. The peptide sequence would be the same d. The resulting peptide...
Below is an mRNA sequence and the peptide it encodes. What would happen if the 7th nucleotide were deleted? 5' GCU-UGU-UUA-CGA-AUU 3' Ala-Cys-Leu-Arg-Ile The entire peptide sequence would change The first amino acid would remain the same, but the others would change. None of the amino acids would change. The first two amino acids would remain the same, but the others would change. > Moving to another question will save this response.
A peptide has the sequence Glu-His-Trp-Ser-Gly-Leu-Arg-Pro-Gly a)name the peptide b)what is the net charge of the molecule at Ph 3,8,12 c) Estimate pl
13. What would be the overall charge of a peptide of the following sequence at pH=5 would be for the peptide Asp-Gly-Arg-His: Asp = 4.1 => EO A)-2 B)-1 bly => 13.1) 9.0 -1 -11 0 C) 0 D) +1 Arg => IL.S ) nis : 4 => "
3. A small peptide has the amino acid sequence Phe-Leu-Tyr-Ala-Leu-Gly-Glu. A shorter variant of this peptide was discovered that had the sequence Phe-Leu-Tyr-Ala; it was demonstrated that this shorter peptide was due to a single base substitution in the second Leu codon. What type of mutation (missense, nonsense, frameshift) gave rise to this shorter peptide? Which of the six possible Leu codons was used in the synthesis of the original (long) peptide (can you eliminate some as possibilities)?
A particular peptide has a stop-transfer sequence in the middle regions of its sequence. The stop- transfer sequence is surrounded by hydrophilic regions on either side and the amino terminal of the peptide contains a few asparagine residues. Describe the orientation of the peptide in the ER membrane. The asparagines and the C-terminal faces the ER lumen The asparagines and the C-terminal faces the cytoplasm The asparagines face the ER lumen, the C-terminal faces the cytoplasm The asparagines face the...