peptide hydrolysis should we know it

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peptide hydrolysis should we know it

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4 Posts

bolognese

10/31/03 - 08:44 AM

hi everyone. i found the following question while studying. i can't remember having read anything similar since i began studying medicine some 10 years ago. just can't understand what it is............... :?: can a similar question appear on the USMLE 1?

What are the smaller digestion products for the following peptide, when using only the chemical, cyanogen bromide (CNBr) for peptide hydrolysis?
H2N-Arg-Ala-Met-Lys-Lys-Met-Gly-Thr-Ile-Trp-Met-Ser-Arg-Lys-COOH

A. H2N-Arg-Ala-Met-Lys-Lys-Met-Gly-Thr-Ile-Trp; Met-Ser-Arg-Lys-COOH

B. H2N-Arg-Ala-Met-Lys; Lys-Met-Gly-Thr-Ile-Trp-Met-Ser-Arg-Lys-COOH

C. H2N-Arg-Ala-Met; Lys-Lys-Met; Gly-Thr-Ile-Trp-Met; Ser-Arg-Lys-COOH

D. H2N-Arg; Ala-Met-Lys; Lys; Met-Gly-Thr-Ile-Trp-Met-Ser-Arg; Lys-COOH

E. H2N-Arg-Ala; Met-Lys-Lys; Met-Gly-Thr-Ile-Trp; Met-Ser-Arg-Lys-COOH

the correct answer is C. why?? i can't tell because i don't know what it is talking about :?: :?: :?:

alice8
Forum Guru

Topics: 37
Posts: 643

10/31/03 - 08:59 AM

Specific chemicals like Cyanogen Bromide (CNBr) cleaves at Met

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alice8
Forum Guru

Topics: 37
Posts: 643

10/31/03 - 09:13 AM

"bolognese" wrote:
can a similar question appear on the USMLE 1? :?:

...i am not sure about Cyanogen Bromide but Trypsin cleaves at Lys and Arg, and
Chymotrypsin cleaves at Aromatic AAs (Phe, Tyr & Trp) are important in peptid hydrolysis,maybe there will be q's about them

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bolognese

10/31/03 - 02:22 PM

thanx very much alice for the explanation. :lol:

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