tag:blogger.com,1999:blog-37148773.post4904369509355715205..comments2024-03-27T14:50:47.345-04:00Comments on <center>Sandwalk</center>: Monday's Molecule #191Larry Moranhttp://www.blogger.com/profile/05756598746605455848noreply@blogger.comBlogger5125tag:blogger.com,1999:blog-37148773.post-16841706687529965882012-10-24T02:02:19.371-04:002012-10-24T02:02:19.371-04:00Well, I hesitated between photosynthetic reaction ...Well, I hesitated between photosynthetic reaction centers and cytochrome bc1 or b6f complexes, but then Rumraket's answer was already visible.Jean-Marc Neuhaushttp://www2.unine.ch/lbmcnoreply@blogger.comtag:blogger.com,1999:blog-37148773.post-89412239965514867092012-10-23T11:58:38.766-04:002012-10-23T11:58:38.766-04:00Sorry you feel that way. I thought it was pretty o...Sorry you feel that way. I thought it was pretty obvious. How many structures have so many heme groups and quinone-like cofactors? I admit that if you aren't aware of photosystems then you don't have a chance but that's the point.<br /><br />The fact that the heme-like groups were colored green was an important hint.Larry Moranhttps://www.blogger.com/profile/05756598746605455848noreply@blogger.comtag:blogger.com,1999:blog-37148773.post-57020541945381286702012-10-23T08:44:08.376-04:002012-10-23T08:44:08.376-04:00/Mikkel Rasmussen btw, and still not an undergradu.../Mikkel Rasmussen btw, and still not an undergraduate :)Mikkel Rumraket Rasmussenhttps://www.blogger.com/profile/07670550711237457368noreply@blogger.comtag:blogger.com,1999:blog-37148773.post-46492061499593768102012-10-23T02:59:55.364-04:002012-10-23T02:59:55.364-04:00This image is a bad choice. Either you recognize i...This image is a bad choice. Either you recognize it because you have seen the publication or you have no chance. The resolution is too low to identify the many prosthetic groups. There seem to be several heme-like groups and quinones, but this is not enough. You could have used a mobile or movable image.Jean-Marc Neuhaushttp://www2.unine.ch/lbmcnoreply@blogger.comtag:blogger.com,1999:blog-37148773.post-58282424536495868072012-10-22T17:52:51.485-04:002012-10-22T17:52:51.485-04:00This is photosystem I (PSI) from Thermosynechoccus...This is photosystem I (PSI) from <i>Thermosynechoccus elongatus</i>. Only organisms that gain energy through photosynthesis, like plants and cyanobacteria, have such systems. The purpose of the system is to absort light and thus provide energy for the internal biochemistry of the organism. <br /><br />Irreducibly complex structures such as these (like the now famous bacterial flagellum) usually consist of several related homologous proteins and seem to have evolved in a stepwise fashion involving multiple duplication events. The reason they are irreducibly complex now is that their constituent parts have been modified since their origin and have become necessary for the extant structure. Mikkel Rumraket Rasmussenhttps://www.blogger.com/profile/07670550711237457368noreply@blogger.com