From owner-btk-mca@hgmp.mrc.ac.uk Tue Jun 6 17:40:54 2000 Return-Path: Received: by mercury.hgmp.mrc.ac.uk (Postfix, from userid 110) id 5B7E717B0C; Tue, 6 Jun 2000 17:40:54 +0100 (BST) Received: by mercury.hgmp.mrc.ac.uk (Postfix, from userid 6024) id 83FA317A91; Tue, 6 Jun 2000 17:40:52 +0100 (BST) Received: from niobium.hgmp.mrc.ac.uk (niobium [193.62.192.41]) by mercury.hgmp.mrc.ac.uk (Postfix) with ESMTP id 04E16415CA for ; Tue, 6 Jun 2000 17:40:51 +0100 (BST) Received: (from news@localhost) by niobium.hgmp.mrc.ac.uk (8.9.3+Sun/8.8.8) id RAA26730 for btk-mca-list@hgmp.mrc.ac.uk; Tue, 6 Jun 2000 17:40:51 +0100 (BST) X-Authentication-Warning: niobium.hgmp.mrc.ac.uk: news set sender to using -f From: athel@ir2cbm.cnrs-mrs.fr (Athel Cornish-Bowden) X-Newsgroups: bionet.metabolic-reg Subject: Phosphofructokinase controls glycolysis (or not?) Date: 6 Jun 2000 17:40:50 +0100 Organization: BIOSCI/MRC Human Genome Mapping Project Resource Centre Lines: 34 Message-ID: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" X-Trace: niobium.hgmp.mrc.ac.uk 960309651 26728 193.62.192.80 (6 Jun 2000 16:40:51 GMT) X-Complaints-To: news@net.bio.net X-Received: by mercury.hgmp.mrc.ac.uk (Postfix, from userid 6024) id 2E6D917A91; Tue, 6 Jun 2000 17:40:49 +0100 (BST) X-Received: from ir2cbm.cnrs-mrs.fr (ir2cbm.cnrs-mrs.fr [193.50.234.128]) by mercury.hgmp.mrc.ac.uk (Postfix) with SMTP id BA3BF415CA for ; Tue, 6 Jun 2000 17:40:47 +0100 (BST) X-Received: from [193.50.234.80] by ir2cbm.cnrs-mrs.fr via ESMTP (950221.405.SGI.8.6.10/920502.SGI) for id SAA15894; Tue, 7 Jun 2000 18:42:27 +0200 X-Sender: cornish@ibsm.cnrs-mrs.fr X-To: btk-mca@hgmp.mrc.ac.uk To: btk-mca@hgmp.mrc.ac.uk Sender: owner-btk-mca@hgmp.mrc.ac.uk Precedence: bulk Many of us active in this field have felt frustrated that the standard textbooks that biochemistry students around the world read continue to repeat the same old nonsense, such as the idea that phosphofructokinase controls the glycolytic flux (or is it pyruvate kinase? or hexokinase? or all three, as Stryer seems to think?). Part of the problem is that if one points out that this makes little sense one is likely to be thought a member of a far-out group of theoreticians out of touch with the real world. So I have long thought it essential to publicize as widely as possible the purely experimental observation that increasing the activity of phosphofructokinase in fermenting yeast 3.5-fold has *no effect* at all on the flux to ethanol (Heinisch, 1986). After nearly 15 years it doesn't seem to have occurred to most textbook authors that this is a simple experimental fact that their theoretical statements need to be able to cope with. As this is just one of several errors (mostly not specifically related to metabolic regulation) that I have noticed over the years to be very frequent in textbooks, I was amusing myself during April trying to compile some statistics, and I have assembled the results into a series of web pages, of which the phosphofructokinase page is at http://ir2lcb.cnrs-mrs.fr/~athel/rls.htm (with links to the others). I should be interested to know the opinions of subscribers to this group about whether the points I make about rate-limiting steps on the page cited are valid, and, of course, if anyone has views on the others I'll be glad to hear about them also. athel --- .