From fasc.ed from gmail.com Sun Jul 27 15:51:12 2008 From: fasc.ed from gmail.com (fasc.ed@gmail.com) Date: Mon Jul 28 09:41:23 2008 Subject: [Photosynthesis] Hydrogen sulfide bacteria Message-ID: What is the source of energy L. luymesi uses at the bottom of the ocean to split hydrogen sulfide? I assume it is heat energy, and that the hydrogen is used to reduce carbon dioxide. Correct? From fasc.ed from gmail.com Sun Jul 27 15:56:28 2008 From: fasc.ed from gmail.com (fasc.ed@gmail.com) Date: Mon Jul 28 09:41:55 2008 Subject: [Photosynthesis] Photsynthesis Message-ID: In cyclic photosynthesis, purple bacteria use cytochromes to pump hydrogen ions out of the cell. Where do the hydrogen ions come from? I don't think it's hydrogen sulfide, because I thought hydrogen sulfide was only used to replenish chlorophyll's electron when its excited electron is used to reduce NADP to NADPH. Thanks. From fasc.ed from gmail.com Sun Jul 27 15:58:01 2008 From: fasc.ed from gmail.com (fasc.ed@gmail.com) Date: Mon Jul 28 09:42:31 2008 Subject: [Photosynthesis] Purple Bacteria Message-ID: <1db04abe-c319-458d-b7d0-16e4f6eae34c@59g2000hsb.googlegroups.com> Why can't purple bacteria survive where there is oxygen around, even though there is plenty of hydrogen sulfide around, too?