Question

Prin hidroliza carei tripeptide din cele de mai jos se obtine un aminoacid care contine 11,96% azot?
a)alanil-seril-glicina
b)seril-glutamil-cisteina
c)glicil-valil-alanina
d)lisil-alanil-serina
e)aspargil-lisil-cisteina

Answer 1

Fiee R-CH-COOH ; aminoacid monoaminomonocarboxilic
              |
             NH2

%N= 14/(M·100)=11,96
De aici scoatem masa molara M
M=(11,96·100)/14=117 g/moli
==>Masa molara a acidului fara radical adica a -CH-COOH=24+32+14+4=74
                                                                               |
                                                                              NH2
==>Masa molara aradicalului (R)=117-74=43 g/moli
Deci radicalul R va fi CH3-CH2-CH2-
adica propil==>
aminoacidul: CH3-CH-CH-COOH (valina)
                                |     |
                              CH3 NH2

==>tripeptida glicil-valil-alanina c