Chemical Forums

Specialty Chemistry Forums => Biochemistry and Chemical Biology Forum => Topic started by: tortillazilla on October 15, 2020, 11:39:39 PM

Title: D- and L- configuration of amino acids
Post by: tortillazilla on October 15, 2020, 11:39:39 PM

Hello! I'm still confused about how the D- and L- configuration of amino acids are determined. Some references say that counterclockwise CORN is L- and clockwise CORN is D-, while some sources say otherwise.

I tried naming the oligopeptide in the photo and came up with L-phenylalanyl-L-seryl-D-cysteinyl-D-tryptophan. Can someone tell me if this is correct? Thank you so much!

Title: Re: D- and L- configuration of amino acids
Post by: Babcock_Hall on October 16, 2020, 10:08:08 AM

I am not familiar with the acronym CORN.  The L,D system is based on L and D glyceraldehyde, and for the amino acids there is not a perfect correlation between the L,D system and the R,S system.  I did not check all of the configurations, but I disagree with your assignment of cysteine.

Title: Re: D- and L- configuration of amino acids
Post by: tortillazilla on October 17, 2020, 08:34:21 AM

Ooh, totally missed that. Thank you so much!