From owner-photosynthesis@net.bio.net Tue Sep 02 23:00:00 1997 Path: biosci!biosci!not-for-mail From: gov@uiuc.edu (govindjee) Newsgroups: bionet.photosynthesis Subject: Post-Doc Position Date: 3 Sep 1997 16:44:26 -0700 Organization: BIOSCI International Newsgroups for Molecular Biology Lines: 44 Sender: daemon@net.bio.net Approved: larry.orr@asu.edu Distribution: world Message-ID: NNTP-Posting-Host: net.bio.net RESEARCH ASSOCIATE POSITION FOR STUDYING THE MECHANISM OF PHOTOPROTECTION BY PLANTS AND ALGAE. This position is available with Tony Crofts and Govindjee at the University of Illinois at Urbana-Champaign beginning immediately (fall, 1997). The candidate must hold a doctorate degree and must have appropriate training and research experience to engage in a multidisciplinary project dealing with the topic of "How Plants cope with Excess Light". The research will involve biophysical, molecular engineering and biochemical studies of the mechanism of photoprotection by plants,algae and cyanobacteria. The candidate will also have an opportunity to interact with several faculty members at UIUC (Urbana,Illinois) who are associated with our interdisciplinary training grant supported by the National Science Foundation. Candidates must be US citizens or permanent residents of the USA. Applications must include a personal vitae; and a brief statement of research interests and experience. We encourage the candidates to communicate with Govindjee at gov@uiuc.edu and with Crofts at a-crofts@uiuc.edu by E-mail. Please send the application and three letters of recommendation (mark them as CROFTS-GOVINDJEE position) directly to Professor Colin Wraight (Director, Integrative Photosynthesis Training Grant, Department of Plant Biology, 190 ER Madigan Laboratory, 1201 West Gregory Drive, Urbana, IL 61801,USA). The University of Illinois is an equal opportunity educator and employer and specifically encourages applications from women and minorities. Antony R. Crofts (Center of Biophysics and Computational Biology, UIUC, 388 Morrill Hall, 505 South Goodwin Avenue, Urbana, IL 61801,USA; telephone: 217-333-2043; fax: 217-244-6615; URL: http://ahab.life.uiuc.edu) Govindjee (Department of Plant Biology, UIUC, 265 Morrill Hall, 505 South Goodwin Avenue, Urbana,IL 61801,USA; telephone: 217-333-1794; fax: 217-244-7246; URL: http://www.life.uiuc.edu/govindjee/) From owner-photosynthesis@net.bio.net Sun Sep 07 23:00:00 1997 Path: biosci!biosci!not-for-mail From: Chris Burns Newsgroups: bionet.photosynthesis Subject: Photosynthesis Research Contents Volume 52 No. 2 May 1997 Date: 8 Sep 1997 15:38:16 -0700 Organization: BIOSCI International Newsgroups for Molecular Biology Lines: 61 Sender: daemon@net.bio.net Approved: larry.orr@asu.edu Distribution: world Message-ID: NNTP-Posting-Host: net.bio.net Photosynthesis Research Contents Volume 52 No. 2 May 1997 Regular papers Characteristics of photosynthetic carbon metabolism of spikelits in rice. N. Imaizumi, M. Samejima, K. Ishihara...................75-82 Fluorescence detected magnetic resonance of monomers and aggregates of bacteriochlorophylls of green sulfur bacteria Chlorobium sp. J. Psencik, T.J. Schaafsma, G.F.W. Searle, J. Hala......83-92 Spectroscopic characterization of quinone-site mutants of the bacterial photosynthetic reaction center. P.D. Laible, Y. Zhang, A.L. Morris, S.W. Snyder, C. Ainsworth, S.R. Greenfield, M.R. Wasielewski, P. Parot, B. Schoepp, M. Schiffer, D.K. Hanson, M.C. Thurnauer.........................................93-103 Inhibition of CO2-fixation and its effect on the activity of Photosystem II, on D1-protein synthesis and phosphorylation. R. Hollinderbaumer, V. Ebbert, D. Godde...............105-116 Responses of Rubisco activation and deactivation rates to variations in growth-light conditions. J. Ernstsen, I.E. Woodrow, K.A. Mott...................117-125 Screening of chlorina mutants of barley (Hordeum vulgare L.) with antibodies against light-harvesting proteins of PS I and PS II: Absence of specific antenna proteins. B. Bossmann, J. Knoetzel, S. Jansson...................127-136 Isolation and pigment composition of the antenna system of four species of green sulfur bacteria. C. Francke, J. Amesz...................................137-146 Donor side capacity of Photosystem II probed by chlorophyll a fluorescence transients. B.J. Strasser..........................................147-155 Antenna organization in the Rhodopseudomonas acidophila studied by fluorescence induction. C.J. Law, R.J. Cogdell, H.-W. Trissl...................157-165 High-resolution solid-state 13C NMR of the LH1 from Rhodospirillum rubrum. K. Yoza, Z.-Y. Wang, M. Kobayashi, T. Nozawa...........167-173 Historical corner Carotenoid-sensitized photosynthesis: Quantum efficiency, fluorescence and energy transfer. H.J. Dutton............................................175-185 From owner-photosynthesis@net.bio.net Sun Sep 07 23:00:00 1997 Path: biosci!biosci!not-for-mail From: BIOSCI Administrator Newsgroups: bionet.photosynthesis Subject: BIOSCI/bionet miniFAQ & Fundraiser Date: 8 Sep 1997 11:13:25 -0700 Organization: BIOSCI International Newsgroups for Molecular Biology Lines: 235 Sender: daemon@net.bio.net Approved: larry.orr@asu.edu Distribution: world Message-ID: <199709080900.CAA17143@net.bio.net> NNTP-Posting-Host: net.bio.net (LAST REVISION: 30-JUL-95) This BIOSCI "miniFAQ" is designed to answer the questions that come up the *most frequently*. The main BIOSCI FAQ (Frequently Asked Questions) is accessible on the World Wide Web at URL http://www.bio.net/. If you can not find an answer to your question in this or other documentation, the BIOSCI technical support staff answers e-mail queries sent to biosci-help@net.bio.net We can only answer questions about the use of the newsgroups and mailing lists. We unfortunately do not have the staff to do Internet information searches or answer scientific questions. Please post those to the appropriate BIOSCI/bionet newsgroups. Contents: -------- 0) BIOSCI NEEDS YOUR SUPPORT!! 1) Using the WWW to access the BIOSCI/bionet newsgroups. 2) What to do about "spams," i.e., junk mail, ads, etc. 3) Examples of subscribing and unsubscribing to the mailing lists. 4) The BIOSCI user address and research interest directory. 0) BIOSCI NEEDS YOUR SUPPORT!! ------------------------------ BIOSCI's government funding has been expended, and we are now operating solely from advertising revenue that we have raised from our Web site at http://www.bio.net/. We need just a few minutes of your time to help us serve you. You can do two important things which will take very little time for you individually and will immensely help us continue to help you. First, please use our WWW system at http://www.bio.net/ to access the archives. You can post or reply to messages via your Web browser as described in item #1 below. Your usage helps attract sponsors. If you contact any of our sponsors, please be sure to thank them for supporting BIOSCI. It is critical for them to get this feedback if they are to continue their sponsorship for the long term. Second, if you work for a company or organization that provides products or services of interest to the biology community, please pass this message on to your marketing or marketing communications department or other appropriate group. Please ask them to help support BIOSCI by sponsoring our Web site and explain the uses and benefits of the system to the biology community. If they are interested, they can then contact us for further information at our tech support address, biosci-help@net.bio.net. 1) Using the WWW to access the BIOSCI/bionet newsgroups. -------------------------------------------------------- As of 10 December 1995, all BIOSCI/bionet full newsgroups are accessible through the World Wide Web (WWW) at URL http://www.bio.net. One can read and reply publicly or privately to both recent postings and archived messages through one's Web browser if it is configured properly to send e-mail. Each newsgroup is equipped with its own WAIS index. The main BIOSCI home page also has access to the BIO-JOURNALS Table of Contents database WAIS index and the BIOSCI user address database described in another item further below. 2) What to do about "spams," i.e., junk mail, ads, etc. ------------------------------------------------------- BIOSCI is a set of parallel USENET newsgroups (the "bionet" groups), mailing lists, and a hypermail archive at URL http://www.bio.net/. The same postings are distributed on all media (except for a small number of mailing-list-only groups at net.bio.net). Unfortunately it is becoming a despicable practice on the Internet (by a few people out to make a fast buck) to do automated mass postings to thousands of newsgroups and mailing lists. These attempts to grab free advertising are refered to as "spams" in the usual, somewhat boneheaded, net terminology. USENET is more susceptible to this practice, and many spams originate on the USENET groups and then are passed on to the mailing lists. 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For those of you with local USENET news systems, the Web interface will also give you faster access to new newsgroups and recent postings. 3) Examples of subscribing and unsubscribing to the mailing lists. ------------------------------------------------------------------ PLEASE NOTE: The BIOSCI management does NOT act on subscription/unsubscription requests that are posted improperly to the newsgroups and mailing lists. People who do this only bother everyone on the lists to no avail. Please be sure to follow the proper procedures below. Gory details are in the BIOSCI Information sheets on the Web at http://www.bio.net. Below we give an example utilizing the METHODS-AND-REAGENTS list at both of our two BIOSCI sites: Users in the Americas and Pacific Rim countries who use the BIOSCI ------------------------------------------------------------------ node at computer net.bio.net: ---------------------------- A) Determine the "listname" which is the <=8 character mail address ^^^^^^^^^^^^^ for the group. These can be found in the BIOSCI Info. Sheet. For the METHODS-AND-REAGENTS group the mailing address is methods@net.bio.net. The listname is the portion of the address to the left of the @ sign, i.e., "methods". The listname is used with the "subscribe" and "unsubscribe" commands illustrated below. B) Mail all commands in the body of a mail message addressed to biosci-server@net.bio.net. Do NOT send commands to the newsgroup posting addresses! Leave the Subject: line blank, any text on it will be ignored. 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For the METHODS-AND-REAGENTS list the USENET newsgroup name is bionet.molbio.methds-reagnts, thus the appropriate commands are sub bionet-news.bionet.molbio.methds-reagnts unsub bionet-news.bionet.molbio.methds-reagnts These commands are included in a message addressed to mxt@dl.ac.uk, NOT to the newsgroup mailing addresses. As usual, include the text in the body of the message as text on the Subject: line is ignored. To unsubscribe from all the lists at the UK node, use unsub bionet-news Please note that if the address in the list is different than the one in your mail message header, you will not be able to unsubscribe by this method. If you have problems, please mail biosci@daresbury.ac.uk. 4) The BIOSCI user address and research interest directory. ----------------------------------------------------------- Please take this opportunity to add your name, address, and research interest information to the BIOSCI User Address Database if you have not already done so. You can fill out the address form directly through our Web page at URL http://www.bio.net/adrform.html. The address database is reindexed nightly for WWW access (the URL is http://www.bio.net/). If you are not directly on the Internet but can reach it by e-mail, please use our waismail server to access the user directory. waismail use is described above. You can also request a user address form by e-mail from biosci-help@net.bio.net. Please check your database entry from time-to-time to see if your address information is still up-to-date. Because of our limited personnel resources, we ask that you resubmit a *complete* form to revise your entry; we only replace complete entries and do not have resources to edit old forms. From owner-photosynthesis@net.bio.net Mon Sep 08 23:00:00 1997 Path: biosci!biosci!not-for-mail From: "Nigel B. Pickering" Newsgroups: bionet.photosynthesis Subject: Wanted: LI-COR 6200 Date: 9 Sep 1997 11:29:23 -0700 Organization: Soil & Water Engr. Tech. Lines: 17 Sender: daemon@net.bio.net Approved: larry.orr@asu.edu Distribution: world Message-ID: <5v44i3$erf@net.bio.net> NNTP-Posting-Host: net.bio.net Hello All Does anyone have a used, good condition, LI-COR 6200 for sale? Or where we might get one? Alternatively, anyone willing to rent one to us for 6 one-week periods over the next 2 years? Nigel -- Nigel Pickering Soil & Water Engineering Technology nbpickering@swet.com From owner-photosynthesis@net.bio.net Thu Sep 11 23:00:00 1997 Path: biosci!biosci!not-for-mail From: Ulrich Sperling Newsgroups: bionet.photosynthesis Subject: annual chl production? Date: 12 Sep 1997 08:34:52 -0700 Organization: ETHZ Lines: 18 Sender: daemon@net.bio.net Approved: larry.orr@asu.edu Distribution: world Message-ID: <34192C9E.6F94@ipw.biol.ethz.ch> NNTP-Posting-Host: net.bio.net Dear all, who wants to volunteer to estimate the global annual chlorophyll production? The most recent estimation I am aware of is 115 Mio to (Hendry et al., New Phytol. (1987) 107, 255 - 302), but earlier papers suggested up to 10 exp 12 tons. So, what are the latest figures? Maybe, all the satellites up there have provided us with new insights into this. Thank you for all your replies to the newsgroup or ulrich.sperling@ipw.biol.ethz.ch Ulrich Sperling Institute for Plant Sciences Swiss Federal Institute of Technology (ETH) Zurich/Switzerland From owner-photosynthesis@net.bio.net Sun Sep 14 23:00:00 1997 Path: biosci!biosci!not-for-mail From: r.s.perry@ic.ac.uk (Robin Perry) Newsgroups: bionet.photosynthesis Subject: iron(II) as p/s electron donor Date: 15 Sep 1997 09:09:31 -0700 Organization: Imperial College Lines: 21 Sender: daemon@net.bio.net Approved: larry.orr@asu.edu Distribution: world Message-ID: <5vjmjr$pli@net.bio.net> NNTP-Posting-Host: net.bio.net A colleague of mine claimed that he has seen a recent paper regarding the use of iron(II) as a primary electron donor in purple non-sulphur iron bacteria. Is anyone aware of such a publication or any information that may relate iron(II) to these orgainsms other than the presence of iron in the quinone elements of the redox chain? If so I would grateful if you could inform me of such activity by e-mail. thanks in advance, Robin Perry (rsperry@ic.ac.uk) -- Mr R.S. Perry Earth Resources Engineering Imperial College London UK email: rsperry@ic.ac.uk From owner-photosynthesis@net.bio.net Sun Sep 14 23:00:00 1997 Path: biosci!biosci!not-for-mail From: Bob Blankenship Newsgroups: bionet.photosynthesis Subject: Re: iron(II) as p/s electron donor Date: 15 Sep 1997 12:07:36 -0700 Organization: BIOSCI International Newsgroups for Molecular Biology Lines: 46 Sender: daemon@net.bio.net Approved: larry.orr@asu.edu Distribution: world Message-ID: NNTP-Posting-Host: net.bio.net Here are two refs that discuss these newly discovered bacteria. To the best of my knowledge, there have not been any other publications on them. Bob Blankenship Widdel, F., Schnell, S., Heising, S., Ehrenreich, A., Assmus, B., and Schink, B. (1993) Ferrous Iron Oxidation by Anoxygenic Phototrophic Bacteria. Nature, 362, 834-836. Ehrenreich, A., and Widdel, F. (1994) Anaerobic oxidation of ferrous iron by purple bacteria, a new type of phototrophic metabolism. Applied and Environmental Microbiology, 60, 4517-4526. >A colleague of mine claimed that he has seen a recent paper regarding the >use of iron(II) as a primary electron donor in purple non-sulphur iron >bacteria. Is anyone aware of such a publication or any information that >may relate iron(II) to these orgainsms other than the presence of iron in >the quinone elements of the redox chain? If so I would grateful if you >could inform me of such activity by e-mail. > > thanks in advance, > > Robin Perry (rsperry@ic.ac.uk) > >-- >Mr R.S. Perry >Earth Resources Engineering >Imperial College >London >UK > >email: rsperry@ic.ac.uk Prof. Robert E. Blankenship Department of Chemistry and Biochemistry Arizona State University Tempe, AZ 85287-1604 USA (602) 965-1439 (602) 965-2747 fax blankenship@asu.edu http://photoscience.la.asu.edu/photosyn/faculty/blankenship.html From owner-photosynthesis@net.bio.net Sun Sep 14 23:00:00 1997 Path: biosci!biosci!not-for-mail From: Vittorio Ernesto Brando Newsgroups: bionet.photosynthesis Subject: macroalgae radiance spectra Date: 15 Sep 1997 09:54:05 -0700 Organization: Universita' Ca' Foscari Venezia Lines: 16 Sender: daemon@net.bio.net Approved: larry.orr@asu.edu Distribution: world Message-ID: <199709151624.SAA16237@helios.unive.it> NNTP-Posting-Host: net.bio.net actually i'm involved in a hyperspectral remote sensing project on the recognition of macroalgae in a shallow brackish water basin: does anybody can give me any reference on the possibility to 'sinthetize' a radiance spectrum of a given algae from the photosinthetic pigments ? thanks in advance Vittorio E. Brando brando@unive.it http://helios.unive.it/~brando ______________________________________________________________ {W} Dip. di Scienze Ambientali | [H] S.Marco, 3536 {O} Universita' di Venezia | [O] 30124 Venezia ITALIA {R} Dorsoduro 2137 | [M] tel ++39-41-5207043 {K} 30123 Venezia ITALIA | [E] fax ++39-41-5269234 From owner-photosynthesis@net.bio.net Mon Sep 15 23:00:00 1997 Path: biosci!biosci!not-for-mail From: "C. A. Rebeiz" Newsgroups: bionet.photosynthesis Subject: Posting of the Chlorophyll Biosynthetic Pathway Date: 16 Sep 1997 16:34:20 -0700 Organization: BIOSCI International Newsgroups for Molecular Biology Lines: 24 Sender: daemon@net.bio.net Approved: larry.orr@asu.edu Distribution: world Message-ID: <5vn51s$260@net.bio.net> NNTP-Posting-Host: net.bio.net In addition to the menu-driven review of the chlorophyll a biosynthetic pathway, and sections on botanical fallouts, Biological significance and Development of Photobiotechnologies, two sections (X and XI) dealing with chlorophyll b biosynthetic pathway have been posted to the Website: "http://w3.aces.uiuc.edu/nres/lppbp". Double Click on the "GREENING PROCESS" link to get there. Have fun. ================================================== C. A. Rebeiz University of Illinois 240A, ERML 1201 West Gregory Avenue Urbana IL. 61801 Telephone: (217)333-1968 Fax: (217)244-5625 Email: CRebeiz@uiuc.edu Home Page: http://w3.aces.uiuc.edu/NRES/LPPBP/ ================================================== From owner-photosynthesis@net.bio.net Sat Sep 20 23:00:00 1997 Path: biosci!biosci!not-for-mail From: taras@mars.biophys.msu.ru Newsgroups: bionet.photosynthesis Subject: double-flash fluorometer Date: 21 Sep 1997 13:04:42 -0700 Organization: Biophys. Dep. MSU Lines: 9 Sender: daemon@net.bio.net Approved: larry.orr@asu.edu Distribution: world Message-ID: <12CFACDA.7220@mars.biophys.msu.ru> NNTP-Posting-Host: net.bio.net Visit our WWW site where you'll find information about double-flash method and fluorometers designed and manufactured by Ecomonitor: http://mars.biophys.msu.ru/primprod/ Good trip through the Web. Head of laboratory of biophysical electronics, Yu. Konev From owner-photosynthesis@net.bio.net Wed Sep 24 23:00:00 1997 Path: biosci!biosci!not-for-mail From: Chris Burns Newsgroups: bionet.photosynthesis Subject: Photosynthesis Research Contents Volume 52 No. 3 June 1997 Date: 25 Sep 1997 08:53:48 -0700 Organization: BIOSCI International Newsgroups for Molecular Biology Lines: 63 Sender: daemon@net.bio.net Approved: larry.orr@asu.edu Distribution: world Message-ID: NNTP-Posting-Host: net.bio.net Photosynthesis Research Contents Volume 52 No. 3 June 1997 Regular papers Electron flow accompanying the ascorbate peroxidase cycle in maize mesophyll chloroplasts and its cooperation with linear electron flow to NADP+ and cyclic electron flow in thylakoid membrane energization. B. Ivanov, G.E. Edwards..........................187-198 Acceptor side photoinhibition in PS II: On the possible effects of the functional integrity of the PS II donor side on photoinhibition of stable charge separation. A. Napiwotzki, A. Bergmann, K. Decker, H. Legall, H.-J. Eckert, H.-J. Eichler, G. Renger........................................199-213 A Fourier transform infrared spectroscopic study of the effects of hydrogen peroxide and high light on protein conformations of Photosystem II. H. Zhang, Y. Yamamoto, Y. Ishikawa, W. Zhang, G. Fischer, T. Wydrzynski........................215-223 Pressure effects on absorption spectra of the isolated reaction center of Photosystem II. B. Gall, A. Ellervee, M. Tars, H. Scheer, A. Freiberg......................................225-231 Over-expression of chloroplast-targeted Mn superoxide dismutase in cotton (Gossypium hirsutum L., cv. Coker 312) does not alter the reduction of photosynthesis after short exposures to low temperature and high light intensity. P. Payton, R.D. Allen, N. Trolinder, A.S. Holaday.....................................233-244 Model studies on the exited state equilibrium perturbation due to reaction center trapping in Photosystem I. R.C. Jennings, G. Zucchelli, R. Croce, L. Valkunas. L. Finzi, F.M. Garlaschi...........245-253 Photosynthetic electron transport and carbon-reduction-cycle enzyme activities under long-term drought stress in Casuarina equisetifolia Forst. & Forst. J. Sanchez-Rodriquez, R. Martinez-Carrasco, P. Perez.. ......................................255-262 Technical communication A method for measuring whole plant photosynthesis in Arabidopsis thaliana. R.A. Donahue, M.E. Poulson, G.E. Edwards.........263-269 From owner-photosynthesis@net.bio.net Sun Sep 28 23:00:00 1997 Path: biosci!biosci!not-for-mail From: Joe Berry Newsgroups: bionet.photosynthesis Subject: A Question Date: 28 Sep 1997 20:58:57 -0700 Organization: BIOSCI International Newsgroups for Molecular Biology Lines: 68 Sender: daemon@net.bio.net Approved: larry.orr@asu.edu Distribution: world Message-ID: <9709282059.AA01736@biosphere.Stanford.EDU> NNTP-Posting-Host: net.bio.net Dear Photosynthesis Researchers, I received an interesting question that might be a useful topic for discussion on the photosynthesis net. The question comes from an astronomer via Maxine Singer, President of the Carnegie Institution. Allan Sandage at the Observatories sent me the following question. Can you help with an answer? He doesn't 'do' email, so email me the answer and I will send it on to him. "Why are plants green?? (I suppose this means and not yellow or blue or red) What evolutionary advantage does green have re photosynthesis?" THanks, Maxine I would appreciate hearing the thoughts of other photosynthesis researchers. I have included my answer and a response from Winslow Briggs below. Thanks, Joe Berry Carnegie Institution of Washington Stanford, CA 94305 joeberry@biosphere.stanford.edu An Answer: Here is one way to look at it: Chlorophyll's absorption is at wavelenths <700 and >400 nm. This "window" was probably prescribed by the chemistry of the primordial oceans. These are thought to have contained high concentrations of Fe+2 ion (which absorbs strongly at wavelengths >700 nm) and dissolved organic compounds (which absorb in the blue and near UV). Thus, chlorophyll is a pigment that "fits" into a window of available light energy. In this sense, it is ideally suited for photosynthesis. On the other hand, chlorophyll is green because it dosen't completely fill the window. This is not an advantage, and plants have evolved a number of accessory pigments to fill the hole in the chorophyll absorption spectrum. These pigments donate absorbed photon energy to chorophyll. __________________________________________________________________ Subject: Re: (Fwd) Question Author: "Winslow Briggs" at Internet Date: 9/25/97 11:26 AM Let me add to Joe's comment: There aren't any conjugated double bond pigments that I know that have extremely broad absorption bands. Below 400nm, the increasing energy of the photons raise the spectre of photochemical damage. Beyond 700 nm, the energy levels are sufficiently low that except in exceptional cases they are insufficient for effectively driving photochemistry. A compromise: an absorption band safely above the UV, and one sufficiently down in the red that useful photochemistry is still possible. My guess is that a single band in either wavelength region would probably be selected against. The situation in higher plants is not perfect, as Joe points out, and accessory pigments are made in some algae to fill in the gaps. Even higher plants use carotenoids, absorbing in the blue, to enhance energy capture, but these still do not extend too far into the green window left by chlorophyll. It seems to me that given the properties of conjugated double bond systems in absorbing light energy, making a molecule with two major bands within the biologically constrained wavelength range is not all that simple, and chlorophyll is an ideal solution. (Note the waving of hands!). From owner-photosynthesis@net.bio.net Sun Sep 28 23:00:00 1997 Path: biosci!biosci!not-for-mail From: amattoo@asrr.arsusda.gov (Autar Mattoo) Newsgroups: bionet.photosynthesis Subject: A postdoctoral position is open Date: 29 Sep 1997 12:00:07 -0700 Organization: BIOSCI International Newsgroups for Molecular Biology Lines: 46 Sender: daemon@net.bio.net Approved: larry.orr@asu.edu Distribution: world Message-ID: <60otrn$shj@net.bio.net> NNTP-Posting-Host: net.bio.net We are looking for a postdoctoral associate to work in my laboratory. The ad is enclosed. PLease bring it to the attention of the promising candidates. Available immediately is a 2-year postdoctoral research associate position in the USDA's Vegetable Laboratory at Beltsville, Maryland 20705-2350. The position is open to US citizens. Citizens of those countries having treaties with US Govt may also apply. The position is in a research program devoted to produce transgenic vegetables (tomato, potato) using novel gene constructs to protect plants against environmental stresses such as high light, drought and oxidative stress, and increase shelf-life and nutritional quality of the produce. Biochemical amd molecular approaches need to be designed and applied. The candidate should be able to work independently and in team research. Background information on the research interests of the principal investigator may be obtained from the net: http://www.barc.usda.gov/psi/vl/home.htm Salary: $38,330 p.a. Send updated resume's and three letters of references to Dr. Autar Mattoo, Research Leader, Vegetable Laboratory, Building 010A, Room 240, USDA, Beltsville Agricultural Research Center, Beltsville, MD 20705-2350, USA. Thanks and with best wishes, Autar (Autar K. Mattoo) The USDA's Vegetable Laboratory Building 010A, Room 246 ARS/PSI/BARC-W 10300 Baltimore Ave Beltsville, MD. 20705-5374, USA Tel: 1-301-504-7380; Fax: 1-301-504-5555 Email: amattoo@asrr.arsusda.gov Internet: http://www.barc.usda.gov/psi/vl/home.htm Better to light a candle than to curse the darkness.....A Chinese Proverb By losing present time, we lose all time.....W. Gurney Benham Generous minds do not amuse themselves with the petty toys of rank, honor, and titles.....Francis De Sales Let noble thoughts come to us from every side...Rigveda, I-89-i From owner-photosynthesis@net.bio.net Tue Sep 30 23:00:00 1997 Path: biosci!biosci!not-for-mail From: George Bowes Newsgroups: bionet.photosynthesis Subject: Why plants use 400-700 nm Date: 1 Oct 1997 13:59:15 -0700 Organization: BIOSCI International Newsgroups for Molecular Biology Lines: 18 Sender: daemon@net.bio.net Approved: larry.orr@asu.edu Distribution: world Message-ID: <199710011945.MAA12250@net.bio.net> NNTP-Posting-Host: net.bio.net The question that Joe Berry raised as to why plants are pretty much restricted to 400-700 nm is one that I ask my biology students, but I broaden it to includ e animals. The eye uses essentially the same small region of the electromagneti c spectrum. My answer would be similar to Winslow Briggs:too much photochemist ry at short wavelengths and too little at longer wavelengths. However, I wonde r if Chl's restricted range is that much of a problem. Chl does absorb, althoug h poorly, in the green and many plants exist in canopy situations. This means t hat in a closed canopy I understand that over 90% of the photons in the 400-700 nm region can be absorbed. If this is so, the antenna pigments are doing a pr etty good job. Or am I being naive? George Bowes Dept Botany, University of Florida Gainesville, Fl 32611 Tel +1 352 392 7919 Fax: +1 352 392 3993