Talk:Pepsin

Invalid Article
According to the Encyclopedia Britannica, "Pepsin was first recognized in 1836 by the German physiologist Theodor Schwann. In 1930 it was crystallized and its protein nature established by John H. Northrop of the Rockefeller Institute for Medical Research." So, it was not discovered in 1993 by Jimmy Park lol. Pepsi was named after pepsin in the 1890's, which is like a 100 years before 1993!!!

hi im melissa. . . if anyone can help me to find out what is the origin of the name pepsin?! if you could let me know. . .that would be great. thanks. email me: email removed to prevent spam &mdash;Vanderdecken∴ &int;  &xi;  &phi;   17:25, 14 June 2006 (UTC) i need it for a biology project

hey i wanted to know that if pepsin digests proteins. It is also a protein so why doesn't it get dissolve in itself?? mail me at : email removed to prevent spam &mdash;Vanderdecken∴ &int;  &xi;  &phi;   17:25, 14 June 2006 (UTC)

I know that there is a phenomenon of autolysis when one pepsin molecule is an substrate and another is an enzyme. So pepsin "eats" itself. To avoid autolysis solution of proteases store at -20 -70 degrees in refregerator.

Sergey, Moscow State University, Department of chemistry, branch of Chemical Enzymology.

I have really four questions, that should further clarify this good article:


 * what is the mechanism, that pepsin does not digest the stomach (lining) itself
 * what are the ideal pH and temperature, where pepsin has its maximum activity
 * before lysing proteins into amino acids, the cell walls must be lysed. is that also an activity of pepsin? or is ther e another enzyme providing this function
 * is there pepsin in coke and pepsi? if so, how much?

massa 09:23, 2 February 2006 (UTC)

(Warning: This user Mens rea v Cheung maintains a strict policy condemning all personal attacks. Any deletions without writer's permission is a challenge to the freedom of speech of Wikipedia. User reserves the right to prosecute and appeal any vandalisms to her works to the Wikipedia founder, Mr Jimmy Wales and so on.)


 * I'm quite sure there is no pepsin in coke and pepsi.
 * I heard that drinking too much of Hong Kong "Vita Lemon Tea" will damage human's memories, how much is it true? Anybody knows?
 * Is there linkage in between "think" and hair quality? People said thinking too much will make a man bald? How much is it true?
 * How to prevent our memories from declining? What kinds of exercises can be done to strengthen our memories?

Mens rea v Cheung 21:30, 22 February 2006 (Home)


 * I really cannot understand the purpose of this questions in this discution/article. Are they by any means connected to the subject of pepsin? jοτομικρόν (talk, email) 17:26, 28 November 2006 (UTC)

Pepsin In Pigs?
I read somewhere that pepsin is a milk-coagulating enzyme found in pig's stomach. Can someone please verify? Thanks. -Velen117 10:28, 16 September 2006 (UTC)
 * See here. - ∅  ( ∅ ), 15:27, 21 December 2006 (UTC)

what is the synonymes of pepsin

medical/diseases
somebody might want to check that. I AM EXPERT, HO does not seem to me to be a disease —The preceding unsigned comment was added by 64.231.115.87 (talk) 14:35, 3 February 2007 (UTC).

acidity vs. activity
The article says in the Storage section that pepsin's activity returns at pH6. The See Also section however, states that the enzyme denaturates at any pH above 5. pH 5 is ten times more acidic than pH 6, so the statements contradict each other, right?

Skogstokerier (talk) 14:55, 8 December 2007 (UTC)

Also, "Pepsin functions best in acidic environments because it is found in an acidic environment"... wtf? Not quite the best logic. —Preceding unsigned comment added by Therealsarsi (talk • contribs) 19:41, 7 May 2008 (UTC)

Pepsinogen
Pepsinogen is not Pepsin. Why does Pepsinogen direct here and why doesn't the page say what pepsinogen is? —Preceding unsigned comment added by 80.216.65.92 (talk) 10:40, 17 May 2008 (UTC)
 * Pepsinogen is a protein that becomes pepsin when exposed to the chemical environment in the stomach. Pepsinogen redirects here because its only purpose is to be a form of pepsin that can be secreted by a gland without damaging the gland. While pepsinogen does not have the same activity that pepsin does, it is literally one step in synthesis away from being pepsin. Also, the page DOES say this. 216.82.142.13 (talk) 19:55, 5 September 2011 (UTC)

cut site
according to some information and book, pepsin cut N-terminal of Phe, Tyr, Trp, not C-terminal of them Ref: Lehninger, Principle of Biochemistry, 4e, p.658 —Preceding unsigned comment added by Noelyuan (talk • contribs) 03:00, 3 July 2008 (UTC)

This information is poorly worded. Pepsin cleaves on the N-terminal side of hydrophobic amino acids, especially aromatic (Phe, Tyr, Trp), and has a preference for cleavage between hydrophobic amino acid pairs. Signed, D.J. Wright, PhD — Preceding unsigned comment added by 50.195.12.153 (talk) 19:26, 31 January 2017 (UTC)

how many human pepsinogen groups there is
I just send an email to a fellow researcher: that was my mail: Hi dear researcher and co-author of the paper « Significance of Serum Pepsinogens as a Biomarker for Gastric Cancer and AtrophicGastritis Screening: A Systematic Review andMeta-Analysis », you did write the following in your introduction: « Human pepsinogens are proenzymes for pepsin, a digestive enzyme produced by gastricchief cells. Human pepsinogens are biochemically and immunochemically classified into twogroups: pepsinogen I (PGI) and pepsinogen II (PGII) ». The problem is when i read some other papers on the subject of pepsinogens I can sometime see another group so called pepsinogen III. My question is the following : is it a mistake to say that there is only two groups of human pepsinogens ?

Best regards,

If you know the answer please talk hereWalidou47 (talk) 18:41, 1 December 2019 (UTC)