Talk:Tyrosine

Polar/Non-Polar

This discussion has already taken place on the Amino Acid page, so I won't repeat it here.

Well? This strange caveat should be mentioned in the article (I don't understand it myself, so I'm afraid to edit it in) or there should, at least, be consistency between the two pages. Thanks. --Meta 3:07, 20 Jan 2011 (UTC) —Preceding unsigned comment added by 204.140.154.86 (talk)

Questions

Has anyone ever tried or heard of using tyrosine to help darken the mouth pigment in dogs? What is the pKa of tyrosine? This should be listed on the information page.66.42.177.162 (talk) 00:08, 1 April 2011 (UTC) Does tyrosine accumulate in the body (organs) or is it water soluble?

metabolism?

It'd be nice to see some more information on the metabolic effects in humans. I see this is included in certain energy drinks, so it would be good to know it's effect. The current article has little detail.

You can enhance your vigilance a little bit, if you swallow l-tyrosine pills. 500-1000 g are the right dose. Tyrosine is changing in adrenalin and melanin. Also it gets metabolize in hormones for the gland of thyroid. Your blood.pressure gets enhanced! --Fackel 20:47, 30 May 2006 (UTC)

-->I think you mean 500 - 1000 milligrams

--> lol, yeah we may have lost a couple of the more trusting wikiers due to that mistake...

Medical Usage

What medical uses are there for tyrosine? I also read that it can promote the division of cancer cells, especially malignant melanoma.

Not really... since it's an essential amino acid it is absolutely required by the human body. You might be talking about tyrosine kinases, enzymes that make the tyrosine phosphorylated (adds a phosporus). That would be a good article to link to from here. --Antorjal 05:00, 5 September 2006 (UTC)

Tyrosine is NOT an EAA. As the article states it's synthesized from phenylalanine. I know this is old but I felt this should be stated so no one gets confused. DriverDan (talk) 18:45, 6 June 2009 (UTC)

I found out that thyrosine helps in nemaline myopathy. I think this info should be added as a medical use. I am looking for the info on such usage but there seems to be no other info except just stating this fact that it helps. But the question is why it helps? Maybe someone has an idea... — Preceding unsigned comment added by 83.11.125.35 (talk) 23:47, 25 November 2011 (UTC)

Enzymatic hydroxylation to give m- and o- isomers??

The current graphic has something about "enzymatic" hydroxylation to give ortho- and meta-isomers. I dont know of any evidence for this hydroxylation being directed by enzymatic processes vs some normal free radical degradation. So I am questioning the validity of the graphic.--Smokefoot 22:21, 22 October 2007 (UTC)

• I just updated the graphic based on the previous version. Perhaps the graphic is not as clear as it should be, but it should be interpreted as enzymatic oxidation leading only to the para isomer (this needs to be verified) whereas free radical oxidation (represented by HO^.) leads to ortho and meta (as well as para). Boghog2 22:26, 22 October 2007 (UTC)

• I revised the figure to make it clearer that enzymatic oxidation by phenylalanine hydroxylase only refers to the top reaction. The second and third arrows refer to free radical oxidation. I hope this eliminates the confusion. Cheers. Boghog2 06:54, 23 October 2007 (UTC)

daily dose?

Suggests (without citation) 100mg/kg per day, then says this is equivalent to 500-1500mg per day. So the average adult wieghs between 5kg and 15kg? Either a typo in the dose or in multiplying the dose up for the daily amount. Also, since it claims that the dose/kg is supported by literature this shouldnt be included without a citation.172.201.254.138 11:37, 1 December 2007 (UTC)

• The 500-1500mg per day is the dosage suggested by manufacturers. The dosage of 100mg/kg per day appears in clinical studies. I added citation of clinical study to treat depression with tyrosine where that dosage was used.--Nawojka (talk) 12:41, 26 March 2008 (UTC)

Cocaine and Tyrosine?

I have recently added a line about Cocaine and Tyrosine, suggesting that taking Tyrosine after using Cocaine can reduce the "hangover" and depression effects associated with Cocaine usage This addition was deleted, and I am not sure why I have seen it used many times and produce positive results

I believe that this is an important piece of information, and that it is relevant, I was wondering if anybody objects that I will add it again?

it is a problem to talk about Drugs?

Cocaine stimulate the creation of Dopamine. and Dopamine creation uses tyrosine, and the body has limited ability to create tyrosine. Most Cocaine users don't eat regularly, and as a result lack the Tyrosine. user:Vishvash —Preceding comment was added at 00:20, 16 January 2008 (UTC)

Would it be useful in helping people to withraw from and stop using cocaine if they are addicted? —Preceding unsigned comment added by 69.120.107.230 (talk) 05:05, 28 January 2008 (UTC)

Casein

If tyrosine "is found in large quantities in casein," then why is there no mention of tyrosine in the casein article? I think there's a difference between saying that tyrosine is "found in large quantities in casein" and "tyrosine was obtained as a product of the degradation of the protein casein," as the source says. Also, I see no justification for the claim that tyrosine is found in "large quantities" in casein. I'm removing that part immediately. svadhisthana (talk) 20:41, 17 August 2008 (UTC)

CONTRADICTIONS IN MEDICAL USAGE

This section of the article contradicts itself and is very unorganized. Could someone please organize this section in a way that says: "Support For Tyrosine" and "Support Against Tyrosine" ? It's clear that this section is arguing with itself. It's not unfair and it's not fair, it's just confusing and tedious. Thanks.

What?

Tyrosine... "has little if any effect on mood.[10][11][12] The effect on mood is more noticeable in humans subjected to stressful conditions" This contradicts itself. It is almost like saying "It has no effect on mood. The effect on mood is more noticeable..." 109.153.85.226 (talk) 13:42, 12 March 2012 (UTC)

Is the 3D image correct? There's a Nitrogen with 4 bonds and no Hydrogen at the end. — Preceding unsigned comment added by Elsurexiste (talk • contribs) 23:10, 14 June 2012 (UTC)

Natural Amphetamine?

Tyrosine seems very close to the structure of amphetamine. It would be interesting to see a study seeing if it has similar effects as amphetamine does. Havabighed (talk) 06:47, 5 July 2012 (UTC)

Diagrams

The ball-and-stick representation doesn't seem to tally with the structural depiction. In particular, the bit that's supposed to be NH₂ has 3 hydrogens on it. — Preceding unsigned comment added by 194.39.218.10 (talk) 15:07, 22 October 2012 (UTC) Sorry, scrub that. I just looked up zwitterion! — Preceding unsigned comment added by 194.39.218.10 (talk) 15:10, 22 October 2012 (UTC)

They are two different ways of depicting the same compound. The first diagram is the typical depiction of an amino acid - with a neutral amino group and a neutral carboxylic acid. But since the amino group is a base and the carboxylic group is an acid, in reality the compound is more likely to exist as an ammonium carboxylate, as depicted in the second diagram. Neither is wrong, but maybe it would be best to use a consistent style for the 2D and 3D representations to avoid this type of confusion. -- Ed (Edgar181) 15:13, 22 October 2012 (UTC)

How good is this study?

Reference #21 (http://www.ncbi.nlm.nih.gov/pubmed/12381742) Says that Aspartame is used as the placebo.

According to my Google search: Phenylalanine - University of Maryland Medical Center www.umm.edu › ... › Complementary Medicine Aspartame, found in artificial sweeteners such as Nutrasweet, is a source of phenylalanine. People with PKU should not use aspartame. If you are pregnant, ask

Aspartame contains phenylalanine which turns into Tyrosine. My point is that maybe this study might have used a better placebo and may be biased.

EricStruble (talk) 02:10, 27 February 2013 (UTC)Eric Warren Struble

L-Tyrosine possible uses Thyroid supplement

Wikipedia thyroid hormones "(T3) and (T4) are Tyrosine-Based hormones produced by the thyroid gland" I think there is some important information here about possible uses other than supporting synthesis of brain neurotransmitters. But I don't see any such information in this article about Tyrosine and Thyroid hormones. Please post a reply I am looking for a Thyroid supplement because thyroid cancer runs in my family.urName (talk) 16:51, 31 July 2013 (UTC)

Commercial Synthesis

There needs to be a section on how the Tyrosine Supplements are made. 2602:306:C518:6C40:F04C:9D27:545:1601 (talk) 16:59, 10 January 2014 (UTC)