Question

1) Consult pages 557 -558 and problem 16.3 on page 558 of the attached pages. These pages are not in your current textbook. Draw the condensed structures of the amino acid isoleucine (see Table 16.2 on page 554 of attachment) at the following pH values: (2 pt.) a) pH 4.0 b) pH= 6.0 c) pH = 8.0 CH3 CH2 CH 3-CH Ha N-C-Coo 1 How does the "isoelectric point" of an amino acid affect its solubility in water? 2) (1 pt.) 3) Classify isoleucine's "R group" as hydrophobic or hydrophilic. (1 pt.)

Answer 1

ye a = 4.0 b p -6.0 C P = 8.0 HN-C-CooH ETAPE HN-C-Coo CH₃ Acidic medium (low pH) Citterion Basic medicam Chigh pH) 2) In this, Soluble proteins have a charge on their surfaces At a specific pt the positive and negative changes will bdance and net charge will be cero called as iso electric point and the amino acid or proteins are occurs in the pH range of 5.5 to 8 i-e it has its lowest solubility at its iso klectric point 3) R- group of isoleucine is - CH - CH₂ which no - has polar group. (CH₂) - Therefore it is hydrophobic in nature.