[cartmanike]

Hey guys. I'm taking science through ILC (online correspondence) and I just can't seem to figure out this question.

Complete the following reaction. Draw the structural formulas for the reactants and the product. Label the functional groups and linkages present. (5 marks)
Glycine + valine → ?


I know they're both amino acids, and I'm pretty sure there would be a peptide bond...but how would I go about actually drawing this?

Thanks!
Julie

[DevaDevil]

well, can you find the structures of glycine and valine? (try wiki for example)
then reason again

[cartmanike]

Well, a peptide bond is when the carboyl group reacts with the amino group. Carboxyl being -C=O-OH or -C=O-O-, and amino being -N-H-H or -+N-H-H-H right?

Glycine is NH2CH2COOH
Valine is HO2CCH(NH2)CH(CH3)2-

So would the COOH of glycine react with the NH2 of the valine?

[Nobby]

Yes and also vise versa. Gly-Val  and Val-Gly is possible

-NH2 and COOH of both amino acids can react

[cartmanike]

I'd like to insert my adobe illustrator picture for you guys to see...how do I do that? I think I figured out the question, I just want to make sure...

[DevaDevil]

usually in forums it work like this:
you upload the picture somewhere (imageshack or some other free space)

then [ img]place your link here[ /img]
without the spaces in the brackets

can someone confirm this works here?

[cartmanike]

Got it! Is this right?

[cartmanike]

oops

[Nobby]

One positive charge to much on Nitrogen

NH₃⁺-CH₂CONH-CH((CH₃)₂CH)COO^-

and

NH₃⁺-CH((CH₃)₂CH)CONH-CH₂COO^-

[cartmanike]

sorry...I don't quite understand without a picture, lol. You mean in the middle of the equation? I should take away the +ion of N?

[Nobby]

Yes correct
 Only free NH2 and COOH gives the ammonium salt

[cartmanike]

like this?

[rabolisk]

Correct, although I would put the H below N in the middle to clearly show that the bond is between the oxygen and the nitrogen.

[cartmanike]

Thank you very much, I appreciate it.