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Fenna-Matthews-Olson complex (bacteriochlorophyll a protein) The location of the FMO complex in the membrane remains unknown; a model has been proposed for the partially embedded FMO complex with the 3­fold axis perpendicular to the membrane plane [3]. Tronrud, D.E., Schmid, M.F. and Matthews, B.W. Structure and X­ray amino acid sequence of a bacteriochlorophyll a protein from Prosthecochloris aestuarii refined at 1.9 Å resolution. Li, Y.­F., Zhou, W., Blankenship, R.E. and Allen, J.P. Crystal structure of the bacteriochlorophyll a protein from Chlorobium tepidum. metallo.scripps.edu /PROMISE/FMOC.html   (314 words)

Bacteriochlorophyll - Wikipedia, the free encyclopedia Bacteriochlorophylls are photosynthetic pigments that occur in various bacteria. Groups that contain bacteriochlorophyll conduct photosynthesis, but do not produce oxygen. Bacteriochlorophylls c and d are chlorins, with one reduced pyrrole ring, and the others are bacteriochlorins, with two. en.wikipedia.org /wiki/Bacteriochlorophyll   (79 words)

Optical Characteristics of the Phototroph Thiocapsa roseopersicina and Implications for Real-Time Monitoring of the ... Carotenoids and bacteriochlorophyll a (near 580 nm) cause the strong absorption in the blue-green and green ranges. The insert is a schematic representation of a proposed algorithm for in situ estimation of bacteriochlorophyll a. The area under the baseline drawn from 760 to 930 nm may be used as a measure of the bacteriochlorophyll a concentration. aem.asm.org /cgi/content/full/65/8/3392   (2965 words)

Medical Molecules: Bacteriochlorophyll as a Potential Component in Cancer Treatment SDSC chemist and principal scientist Kim Baldridge is studying bacteriochlorophyll, a substance that can be extracted from certain kinds of bacteria, in a collaboration with graduate student Roie Yerushalmi, a member of Professor Avigdor Scherz's group of the Weizmann Institute of Science in Israel. Bacteriochlorophyll is a form of chlorophyll in some bacteria that performs photosynthesis, the use of light as a source of energy to propel the conversion of carbon dioxide, water, and inorganic salts into complex organic materials like carbohydrates, for sustenance. Another modification is to bond a ligand (an atom or molecule that bonds in an axial manner to the central metal atom) using the bacteriochlorophyll frame to study ligands of biological interest. www.sdsc.edu /~kimb/roieresearch.html   (763 words)

Light Harvesting In green non-sulfur bacteria, a bacteriochlorophyll a containing protein known as the Fenna-Matthews-Olson (FMO) protein is located between the chlorosome and reaction center. The bacteriochlorophyll protein, or FMO protein, from Chlorobium tepidum, that serves as a light harvesting complex that directs light energy from the chlorosomes attached to the cell membrane to the reaction center has been crystallized and the structure has been determined in collaboration with Robert Blankenship. Bacteriochlorophyll 2, that is located near the interface of the protein subunits forming the trimer, is the only cofactor that is coordinated by a water molecule rather than the protein. photoscience.la.asu.edu /Photosyn/faculty/Allen/photosynthesis/light-harvesting.html   (393 words)

Images of Rps. acidophila LH2 The magnesium at the centre of each bacteriochlorophyll molecule is shown as a silvery grey sphere. absorbing bacteriochlorophylls lay closest to the cytoplasm (above left) and are arranged with their chlorin rings parallel to the plane of the membrane (above centre). absorbing bacteriochlorophylls, which are arranged perpendicular to the membrane plane in a ring lay closest to the periplasmic face. www.gla.ac.uk /ibls/BMB/rjc/lh2gallery_pigs.html   (278 words)

Structural studies of Fenna-Matthews-Olson complex Fenna, R.E. and Matthews, B.W. Structure of a bacteriochlorophyll a­protein from Prosthecochloris aestuarii. Fowler, C.F., Gray, B.H., Nugent, N.A. and Fuller, R.C. Absorbance and fluorescence properties of the bacteriochlorophyll a reaction center complex and bacteriochlorophyll a protein in green bacteria. Matthews, B.W., Fenna, R.E., Bolognesi, M.C., Schmid, M.F. and Olson, J.M. Structure of a bacteriochlorophyll a­protein from the green photosynthetic bacterium Prosthecochloris aestuarii. metallo.scripps.edu /promise/FMOC_REF.html   (627 words)

Phototroph Summary Bacteriochlorophyll gave origin to chloroflexus, sulfur green bacteria, sulfur purple bacteria, non-sulfur purple bacteria, and finally to oxygen-respiring bacteria. Photosynthetic bacteria have a substance called bacteriochlorophyll, live in lakes and pools, and use the hydrogen from hydrogen sulfide instead of from water, for the chemical process. (The bacteriochlorophyll pigment absorbs light in the extreme UV and infra-red parts of the spectrum which is outside the range used by normal chlorophyll). www.bookrags.com /Phototroph   (767 words)

intas 93-2810   (Site not responding. Last check: 2007-10-10) This project is a collaborative approach to the synthesis of chlorin and bacteriochlorin photosensitisers, and to the study of their chemical, photophysical and photobiological properties. The project will be carried out as follows: a synthesis of chlorophyll ‘a’; and bacteriochlorophyll ‘a’; a study of photophysical properties; a study of plasma components interaction; and in vito and in vivo PDT evaluation. A feature of the work is to use naturally-occurring substances, chlorophyll and bacteriochlorophyll, as the starting materials, and this direction rests on the experience in the Moscow laboratory in the isolation of photosensitisers from these sources. www.intas.be /catalog/93-2810.htm   (618 words)

Feinberg Graduate School, Weizmann Institute Ashur is investigating a particular bacteriochlorophyll molecule with manganese as its central metal. Katz is investigating bacteriochlorophyll, a molecule synthesized in Prof. Salomon and Scherz, a new family of such pigments was developed based on derivatives of bacteriochlorophyll, the green pigment of photosynthetic bacteria. www.weizmann.ac.il /feinberg/student_research_1998/plant_sciences.shtml   (1094 words)

[No title] Although the activities of many enzymes involved in the pathway have been demonstrated in crude tissue extracts or intact organelles, very few have been purified and characterized(1). On the other hand, much progress in characterizing bacteriochlorophyll synthesis has been made especially in genetic analysis(2). Chl and bacteriochlorophyll are produced from the same precursors by a pathway which is conserved until its later stages. www.lycos.com /info/chlorophyll.html   (883 words)

Bacteriochlorophyll-a derivatives useful in photodynamic therapy - US Patent 5171741   (Site not responding. Last check: 2007-10-10) Bacteriochlorophyll-a (bchla) is a tetrahydroporphyrin found in certain photosynthetic bacteria, for example, Rhodopseudomonas virdis. Bchla is essentially identical to the chlorophyll-a of higher plants except that ring B is in the dihydro form and the vinyl group in ring A is converted to an acetyl group. Bacteriochlorophyll-a, obtained at >90% purity from Porphyrin Products (Logan, Utah) was dissolved at a concentration of 5 mg/ml in Tween-80 (Sigma) by stirring for several hours or overnight. www.patentstorm.us /patents/5171741.html   (3603 words)

National Partnership for Advanced Computational Infrastructure: Archives Bacteriochlorophyll, when illuminated, can cause the light to reach deeper into tissue, thereby being more effective for larger tumors. Unlike chlorophyll, the green matter found in plants, bacteriochlorophyll does not need oxygen for photosynthesis. Bacteriochlorophyll can be modified, both its electronic properties, as well as for basic science, thereby demonstrating both the fundamental principles of chemistry as well as the molecules use in photodynamic therapy. www.npaci.edu /online/v4.8/bacteriochlorophyll.html   (799 words)

Publications Association of tetrapyrrole intermediates in the bacteriochlorophyll a biosynthetic pathway with the major outer membrane porin protein from Rhodobacter capsulatus. Cloning and characterization of the chlorophyll biosynthesis gene chlM from Synechocystis PCC 6803 by complementation of a bacteriochlorophyll biosynthesis mutant of Rhodobacter capsulatus. Characterization of Chlorophyll a and Bacteriochlorophyll a Synthetases by Heterologous Expression in E. www.bio.indiana.edu /~bauerlab/publications.html   (2235 words)

Graduate research The initial step of photosynthesis, transformation of the light energy into a transmembrane potential is facilitated by various proteins, which contain bacteriochlorophyll or chlorophyll and carotenoid pigments. The idea to create this kind of mutation is quite simple- the redox properties of bacteriopheophytin and bacteriochlorophyll are markedly different, bacteriopheophytin is much easier to reduce than bacteriochlorophyll. Nevertheless, the mutation altered the properties of the bacteriochlorophyll, and electron transfer along the B branch was observed. www.public.asu.edu /~evaldas/graduate_research.htm   (1062 words)

Thioredoxin Is Involved in Oxygen-Regulated Formation of the Photosynthetic Apparatus of Rhodobacter sphaeroides -- ... To determine the bacteriochlorophyll content, the cells were sedimented and resuspended in acetone-methanol (7:2, vol/vol). The relative amount of bacteriochlorophyll per cell was calculated as described in Materials and Methods. A redox-responding repressor of bacteriochlorophyll, carotenoid, and light harvesting-II gene expression in Rhodobacter capsulatus. jb.asm.org /cgi/content/full/181/1/100   (4686 words)

Identification of intramembrane hydrogen bonding between 13(1) keto group of bacteriochlorophyll and serine residue ...   (Site not responding. Last check: 2007-10-10) Identification of intramembrane hydrogen bonding between 13(1) keto group of bacteriochlorophyll and serine residue alpha27 in the LH2 light-harvesting complex. Identification of intramembrane hydrogen bonding between 13(1) keto group of bacteriochlorophyll and serine residue alpha27 in the LH2 light-harvesting complex.Nearly half of the 96 chlorophylls have aa residues suitable as hydrogen bond donors to their keto groups. The possibility is discussed that weak H-bonding between the C-13(1) keto carbonyl and a methyl hydrogen of the alanine replacing serine(-4) or the imidazole group of the nearby histidine maintains structural integrity in this very stable bacterial light-harvesting complex. www.pdg.cnb.uam.es /UniPub/iHOP/gp/10040604.html   (169 words)

The bchU Gene of Chlorobium tepidum Encodes the C-20 Methyltransferase in Bacteriochlorophyll c Biosynthesis -- Maresca ... Growth-rate-dependent bacteriochlorophyll c/d ratio in the antenna of Chlorobium limicola strain UdG6040. Oelze, J. Light and oxygen regulation of the synthesis of bacteriochlorophylls a and c in Chloroflexus aurantiacus. Evidence for spatially separate bacteriochlorophyll c and bacteriochlorophyll d pools within the chlorosomal aggregate of the green sulfur bacterium Chlorobium limicola. jb.asm.org /cgi/content/full/186/9/2558   (6445 words)

Characterization of Chlorobium tepidum Chlorosomes: A Calculation of Bacteriochlorophyll c per Chlorosome and Oligomer ... Oligomeric bacteriochlorophyll c as a model for the 740-nm absorbing bacteriochlorophyll-c in Chloroflexus aurantiacus chlorosomes. Isolation of native chlorosomes free of bound bacteriochlorophyll-a from Chloroflexus-aurantiacus by gel-electrophoretic filtration. On the structure of bacteriochlorophyll molecular aggregates in the chlorosomes of green bacteria—a molecular modeling study. www.biophysj.org /cgi/content/full/85/4/2560   (2659 words)

Electrostatic Interactions between Charged Amino Acid Residues and the Bacteriochlorophyll Dimer in Reaction Centers ... The extent of electrostatic contributions from the protein environment was assessed by the introduction of ionizable residues near the bacteriochlorophyll dimer in reaction centers from Rhodobacter sphaeroides. An average dielectric constant of approximately 20 was estimated for the local protein environment, consistent with a relatively hydrophobic environment for residue M199. The rate of charge recombination between the primary quinone acceptor and the bacteriochlorophyll dimer decreased in the M199 Asn to Asp mutant at high pH, reflecting the decrease in midpoint potential. pubs.acs.org /cgi-bin/abstract.cgi/bichaw/2001/40/i50/abs/bi011574z.html   (321 words)

Plant Physiology Online: Structures of Two Bacterial Reaction Centers The two bacteriochlorophylls at the top (P870) are the “special pair” that react with light within the reaction center. The distances between the depicted molecules and their angles within the planes of symmetry of the reaction center have been determined with precision, making it possible to analyze the path of photons and electrons in the reaction center in remarkable detail. Two of the bacteriochlorophyll molecules are in intimate contact with each other and are known as the special pair. 4e.plantphys.net /article.php?ch=t&id=70   (657 words)

Excitation Energy Transfer from Carotenoid to Bacteriochlorophyll in the Photosynthetic Purple Bacterial Reaction ... The overall energy transfer efficiency between the excited carotenoid and bacteriochlorophyll is estimated to be greater than or equal to 75%. The carotenoid in the purple bacterial reaction center is in a 15-cis-configuration, which differs from the all-trans configuration of carotenoids found in the vast majority of antenna systems. The efficient singlet excitation energy transfer observed in this study suggests that the configuration difference is not a key factor in determining the efficiency of carotenoid-to-bacteriochlorophyll singlet excitation energy transfer. pubs.acs.org /cgi-bin/abstract.cgi/jpcbfk/2003/107/i50/abs/jp036130m.html   (314 words)

The paper The antenna system consists of hundreds of pigment molecules (mainly chlorophyll or bacteriochlorophyll and carotenoids) that are anchored to proteins within the photosynthetic membrane and serve a specialized protein complex known as a reaction center. Anoxygenic photosynthetic bacteria depend on bacteriochlorophyll, a family of molecules that are similar to the chlorophyll, that absorb strongly in the infrared between 700 and 1000 nm. The antenna system of the green sulfur bacteria is composed of bacteriochlorophyll and carotenoids and is contained in complexes known as a chlorosomes that are attached to the surface of the photosynthetic membrane. www.life.uiuc.edu /govindjee/paper/gov.html   (12489 words)

2002 LSU-HHMI Summer Undergraduate Research Program Rhodobacter capsulatus, purple non-sulfur photosynthetic bacterium, uses the common tetrapyrrole pathway to synthesize four different tetrapyrroles: bacteriochlorophyll, heme, vitamin B12 and siroheme. When growing photosynthetically, bacteriochlorophyll accounts for more than 98% of all the tetrapyrroles synthesized. It was previously demonstrated that oxygen regulates the intracellular levels of porphobilinogen, the first intermediate committed to tetrapyrrole biosynthesis. www.biology.lsu.edu /hhmiprog/2002/eBaldwin.html   (318 words)

Publication: The bchU gene of Chlorobium tepidum encodes the c-20 methyltransferase in bacteriochlorophyll c ... Publication: The bchU gene of Chlorobium tepidum encodes the c-20 methyltransferase in bacteriochlorophyll c biosynthesis. The bchU gene of Chlorobium tepidum encodes the c-20 methyltransferase in bacteriochlorophyll c biosynthesis. Bacteriochlorophylls (BChls) c and d, two of the major light-harvesting pigments in photosynthetic green sulfur bacteria, differ only by the presence of a methyl group at the C-20 methine bridge position in BChl c. www.fred.psu.edu /ds/retrieve/fred/publication/15090495   (309 words)

Photosynthesis Other photosynthetic organisms, such as cyanobacteria (formerly known as blue-green algae) and red algae, have additional pigments called phycobilins that are red or blue and that absorb the colors of visible light that are not effectively absorbed by chlorophyll and carotenoids. Many antenna pigments transfer their light energy to a single reaction center by having this energy "hop" to another antenna pigment, and yet to another, etc., until the energy is "trapped" in the reaction center. An elegant example of such an approach is the modification of the midpoint redox potential of the bacteriochlorophyll in the reaction center of purple bacteria. photoscience.la.asu.edu /photosyn/education/photointro.html   (5304 words)

UniProtKB/Swiss-Prot entry P26163 [BCHB_RHOCA] Light-independent protochlorophyllide reductase subunit B Burke D.H. Alberti M. Hearst J.E. "bchFNBH bacteriochlorophyll synthesis genes of Rhodobacter capsulatus and identification of the third subunit of light-independent protochlorophyllide reductase in bacteria and plants."; Fujita Y. Bauer C.E. "Reconstitution of light-independent protochlorophyllide reductase from purified bchL and bchN-bchB subunits. Bacteriochlorophyll biosynthesis; Chlorophyll biosynthesis; Direct protein sequencing; Oxidoreductase; Photosynthesis. www.expasy.org /uniprot/BCHB_RHOCA   (302 words)

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