Re: Iddo's test 4, questions 9 and 10

Luis (candeias@graylab.ac.uk)
Wed, 14 Feb 1996 11:41:46 +0100

>> If I understood the questions, they concern the chirality of the=20
>> beta-carbon. I identify the aminoacids as:
>>=20
>> a: L-Thr, configuration of the beta carbon =3D R
>> b: L-Thr, configuration of the beta carbon =3D S (L-alo-Thr)
>>=20
>> c: L-Ile, configuration of the beta carbon =3D R
>> d: L-Ile, configuration of the beta carbon =3D S
>>=20
>The identification of your amino acid's beta carbon as R or S
>is correct. The configuration of the naturally occurring isoleucine
>is not "c" but "d", so in Iddo's test, the correct answer is "2",
>that is "a and d".
>
>An easy way to remember this is to think th"R"eonine and i"S"oleucine!
>

Dear Gayle,
thanks for the correct answers, especially for the nice trick to remember=20
the natural enantiomers.
I'm still wondering: is there any reason for this ?
Luis
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D
- \ Luis Pedro Candeias
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