Talk:Amino acid/Archive 1

Metabolism of amino acids is entirely missing. --Eleassar777 07:37, 3 May 2005 (UTC)
 * I have information on the biosynthesis of most of the amino acids, which I will be including in the relevant articles when I can. Degradation should probably be dealt with here. Physchim62 13:14, 15 July 2005 (UTC)

Please don't tabelize this. If the content is indented, wiki goes ahead and puts it in a fixed-width font. Judicious use of spacing then provides nearly the same benefit of HTML table markup, but with much, much less clutter. This clutter obscures the content when one edits, and may discourage the HTML-averse from contributing.

I question, even, whether the introduction of subscripting for chemical formula is justified--clearly, so far, I've come down in favor of it, but just barely.

OK, go ahead and tabelize this, if you want. I've learned, in the context of the talk:SI derived unit page (or thereabouts) that subscript and superscript tags are not allowed within preformatted text tags (&lt;sup&gt;, etc are not allowed inside of &lt;pre&gt;) which I confirmed by a look at the HTML specs.

The ascii drawing of the ring structure is really nice, so it breaks my heart to not be able to mix super- an subscripts with preformatting. I don't know if we can specify via HTML markup and UseMod wiki a fixed-width font for such pages.

I just put the table tags back in and used the &lt;tt&gt; tag and &amp;nbsp; escape code to simulate preformatted text. I hope this isn't too ugly for future editors and doesn't step on the HTML standards worse than subscripts in &lt;pre&gt; tags did.

I didn't add any new information, so just undo my edit if you don't like it and nothing will be lost.

I think it looks very good. You used a lot of space between elements in the table markup, which I think might aid anyone who would subsequently try to edit it. Thank you.

Most of this side chain ascii-art just sux, and at least Proline is incorect (it's probably imposible to draw it this way) Someone should draw real images and upload them here (the second part seems more difficult) --Taw

Drawing amino acids is actually really easy; you just need a chemistry drawing program. Any chemist should have a commerical one; ISIS/Draw is free for personal use, among other programs. If people really want, I'll make up some suitable image, but it'll be at least a little work, so I'll wait for feedback first -Dlamming

Why the table has been removed ? There are many useful information that can be tabelized like their masses, isoelectric points, type (hydrophobic/hydrophilic) Taw

Whoops. Didn't realize I'd delete the properties together with the table (yes, strange). I put the table back in, without the structure. If you want, go ahead and cut the image into "handy" pieces and put them into the table, but I'm not sure that will improve the whole thing, as some AA images would be quite large. But, that might work on the individual AA pages, once we can upload things right here... --Magnus Manske

Images are ok as they are now. They wouldn't fit easily into table. Taw

Request: could somebody write about all amino acids out of The 20 that are either: Taw
 * important in metabolism, like ornithine
 * part of some proteins, like hydroxyproline

A helpful 3-D modeling program called http://www.mdlchime.com/chime/ CHIME exists for those who explore the tertiary structures. And I have made nice 3d jpgs of ball and stick saccharine and ATP molecules from the CHIME program. Let me know if u want me to try to get the color chimes/jpg of the 20 essentials ok ? ~BF -a closet scientist, but publically New Age !

Could somebody cut (easy part) and upload (hard part) images of individual amino acids. They will be used on pages of each of them some day. Taw - I'd be interested in more information on amino acids other than the standard 20. Particularly:
 * Are there any amino acids not coded by codons in humans, but which are in other lifeforms?
 * Are there any amino acids not found naturally in humans, but present in other species? (I'm not talking about D- vs. L- forms here, but wholly separate amino acides).
 * How many naturally occuring amino acids are known, across all species, other than the standard 20, selenocysteine, ornithine and the D-forms of those? The article mentions that beta forms, but are there any other alpha forms? -- SJK

The genetic code using pretty much the same amino acids in all living things. If you want to go beyond them, you get a whole slough of different compounds, including a variety in humans and a variety in other living things, most of which are different alpha-forms, often slight modifications of the standard 20 (cystine, selenocysteine, hydroxyproline, etc). I'm afraid it would be vain to try and enumerate them all, or even to give a representative list without a biochem text handy, as there is a whole slough of them.

Ok, best I can tell, arginine is not an essential amino acid. The urea cycle is a method of synthesis of this amino acid. Lysine appears to be essential however, and often a limiting amino acid in plants. So I'm making that change in the essential aa list. For those who need further confirmation, please read this abstract. David M


 * Ok, both arginine and lysine may be essential, depending on the reference. I don't have Voet and Voet 2nd ed, but this set of class notes for V&V suggests there are 10 essential aas, including both arginine and lysine. Ugh. I'll keep digging. David M
 * I have a set of class notes with the aside that arginine and histidine are essential only in children. That at least makes some sense. David M

One more point. The isoelectric point isn't nearly as useful as the pK of any ionizable side chains. Those need to be tabulated for any side chain with an actively ionizable group. David M

The plug-in Chime needs to be a Wikipedia entry, so people can be more easily directed to getting it and using it. It makes it possible for people to visualize 3D structures. It also makes it possible for people to use the Protein Data Bank and visualize proteins and enzymes in 3D.Dwmyers

This site is fun (photos of amino acid crystals):
 * The Amino Acid Collection
 * http://micro.magnet.fsu.edu/aminoacids/index.html

David M

But full of misinformation unfortunately. Josh Cherry 04:17, 20 Oct 2003 (UTC)

In the Figure, note error: should be Lys / I, not Lys /L

Should be Lys/K actually. Josh Cherry 04:17, 20 Oct 2003 (UTC)

The Polish version has nice pics. Can somebody place them on the English version? I am not going to do it myself because I don't know enough about the subject. Andries 22:15, 14 May 2004 (UTC)

I know I've heard of amino acids being used as artificial sweeteners and as salt substitutes, but I don't know which aminos. If anyone knows more about this, I think it would be interesting to mention under "Uses of amino acids" Gregchapman 10:33, Aug 8, 2004 (UTC)

Amino acid residue
Interested/knowledgable parties should check out Amino acid residue for possible merging into this article (or just deletion). - dcljr 17:47, 2 Sep 2004 (UTC)

How come some amino acids (H, K, T, W, Y) are shown as both "hydrophobic" and "polar"?

Imino Acid
Strictly speaking, this makes proline an imino acid.

I know that many textbooks make this claim. However, proline is an amine, just not a primary amine. Furthermore, proline is not a imine (the nitrogen analog of an aldehyde or ketone). So, what's the basis for this? Josh Cherry 03:42, 29 Oct 2004 (UTC)

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 * Since a link has been made from ketosis where glucogenic amino acids are mentioned, it is a shame this page doesn't mention which ones those are.--Silverback 20:47, 18 Dec 2004 (UTC)