Publications

iupac-iub commission on biochemical nomenclature (cbn). nomenclature of iron-sulfur proteins. 1973 recommendations.		1973	4351529
the purification and some properties of the molybdenum-iron protein of chromatium nitrogenase.		1973	4352495
electron spin resonance characterization of chromatium d hemes, non-heme irons and the components involved in primary photochemistry.		1973	4355789
"super-reduction" of chromatium high-potential iron-sulphur protein in the presence of dimethyl sulphoxide.		1973	4356972
measurement of the oxidation reduction potential of the epr detectable active centre of the molybdenum iron protein of chromatium nitrogenase.		1973	4357421
the amino acid sequence of cytochrome c' from alcaligenes sp. n.c.i.b. 11015.	the amino acid sequence of the cytochrome c' from alcaligenes sp. n.c.i.b. 11015 (iwasaki's ;pseudomonas denitrificans') has been determined. this organism is the only non-photosynthetic bacterium in which the protein has been found. the protein consists of a single polypeptide chain of 127 residues, with a single haem covalently attached to two cysteines. unlike normal cytochromes c, the haem attachment site is very close to the c-terminus. the amino acid sequence around the haem attachment sit ...	1973	4360249
shifts of bacteriochlorophyll and carotenoid absorption bands linked to cytochrome c-555 photooxidation in chromatium.		1973	4360255
identification of primary photosynthetic processes.		1973	4361883
the bacteriochlorophyll absorption band shifts linked with the energy state of photosynthetic bacteria membranes.		1973	4200406
[higher structure and function of carboxydismutase (author's transl)].		1973	4587673
[tricarboxylic acid cycle enzymes in various species of phototrophic bacteria].		1973	4544539
the fine structure of chromatium buderi.		1973	4121821
iron-sulfur proteins: structure and function.		1973	4599384
nucleotide pools and adenylate energy charge in balanced and unbalanced growth of chromatium.	adenine nucleotide pools and their energy charge were measured during balanced and unbalanced growth of photoheterotrophic chromatium cultures. the methods used involved rapid sampling, accurate to within 1 s, from isotopically labeled cultures followed by chromatographic separation of individual nucleotides. during balanced growth, both energy charge and adenosine triphosphate (atp) concentrations, whether expressed as a function of cell protein or intracellular water, were slightly higher in l ...	1973	4698217
some effects of o-phenanthroline on electron transport in chromatophores from photosynthetic bacteria.		1973	4705131
light-induced absorption changes in chromatium subchromatophore particles exhaustively extracted with non-polar solvents.		1973	4705132
redistribution of electric charge accompanying photosynthetic electron transport in chromatium.		1973	4705448
catalytic role of subunit a in ribulose-1,5-diphosphate carboxylase from chromatium strain d.		1973	4716958
[evidence for the existence of a bacteriochlorophyll regeneration process].		1973	4721712
utilization of amino acids by chromatium sp. strain d.		1973	4732225
the complete amino acid sequence of chromatium high potential iron sulfur protein.		1973	4745771
oxidative formation of phosphoglycolate from ribulose-1,5-diphosphate catalysed by chromatium ribulose-1,5-diphosphate carboxylase.		1973	4748814
[characteristics of proteins (number of chains and molecular weights) of pigment-lipoprotein complexes from chromatium].		1973	4748894
utilization of amino acids by chromatium sp. strain d.		1973	4775033
comparative study of the circular dichroism spectra of reaction centers from several photosynthetic bacteria.		1973	4630407
anion radical of bacteriochlorophyll.		1973	4632875
distribution of the isopropylmalate pathway to leucine among diverse bacteria.	alpha-isopropylmalate synthase and beta-isopropylmalate dehydrogenase activities were detected in extracts of the following organisms: chromatium d, rhodopseudomonas spheroides, hydrogenomonas h16, pseudomonas aeruginosa, pseudomonas fluorescens, vibrio extorquens, rhizobium japonicum, alcaligenes viscolactis, escherichia coli b, proteus vulgaris, aerobacter aerogenes, salmonella typhimurium, micrococcus sp., micrococcus lysodeikticus, bacillus polymyxa, bacillus subtilis, and nocardia opaca. th ...	1974	4829932
[alterations in iron compounds during the evolution of carbon dioxide assimilation].		1974	4831013
determination of oxidation-reduction potentials by spectropolarimetric titration: application to several iron-sulfur proteins.		1974	4831335
[occurrence of phytol and geranylgeraniol in the bacteriochlorophylls of red and green sulfur bacteria (author's transl)].		1974	4836255
two-angstrom crystal structure of oxidized chromatium high potential iron protein.		1974	4855287
d-ribulose-1, 5-diphosphate carboxylase and the evolution of autotrophy.		1974	4613398
[natural electron donors in the process of nitrogen fixation].		1974	4619170
sulfite reductase activity in extracts of various photosynthetic bacteria.	extracts of representative bacterial strains from the various families of photosynthetic prokaryotes are demonstrated to possess significant levels of sulfite reductase [ec 1.8.99.1; hydrogen-sulfide: (acceptor)oxidoreductase] activity with reduced methyl viologen as electron donor, but not nadph(2). the enzyme is localized primarily in the soluble fraction of the extracts, in contrast to adenylysulfate reductase [ec 1.8.99.2; amp, sulfite: (acceptor) oxidoreductase], which is bound normally in ...	1974	4526215
distribution of purple photosynthetic bacteria in wetland and woodland habitats of central and northern minnesota.	enrichment cultures for purple nonsulfur and sulfur photosynthetic bacteria were prepared from soil samples collected in central and northern minnesota. the purple nonsulfur bacteria were found in most wetland soils sampled but were uncommon in woodland and grassland soils. the ph range of the soils in which these bacteria occurred was 3.8 to 7.8, and the oxidation-reduction potential (e(h)) range was +510 to -65 mv. soils with a ph below 5.0 or an e(h) above +370 mv had few purple nonsulfur bac ...	1974	4590487
mössbauer spectroscopy of the nitrogenase proteins from klebsiella pneumoniae. structural assignments and mechanistic conclusions.	the mo-fe protein and the fe protein which together constitute the nitrogenase of klebsiella pneumoniae were prepared from bacteria grown in (57)fe-enriched medium. the mössbauer spectrum of the mo-fe protein, as isolated in the presence of na(2)s(2)o(4), showed that the protein contained three iron species, called m4, m5 and m6. the area of the spectrum associated with species m4, with delta=0.65mm/s and deltae=3.05mm/s at 4.2 degrees k, corresponded to two iron atoms/molecule of protein and it ...	1974	4596139
amino acid sequence of ferredoxin from a photosynthetic green bacterium, chlorobium limicola.		1974	4407619
letter: spectroscopic and magnetic characterization of high potential iron-sulfur protein from chromatium.		1974	4414400
comparison of oxidation-reduction site geometries in oxidized and reduced chromatium high potential iron protein and oxidized peptococcus aerogenes ferredoxin.		1974	4417854
methylrhodibalamin and 5'-deoxyadenosylrhodibalamin, the rhodium analogues of methylcobalamin and cobalamin coenzyme.		1974	4425457
isolation and characterization of chromatium vinosum membranes.		1974	4447429
the covalently bound flavin of chromatium cytochrome c552. 2. sequence of flavin peptides and flavin-tyrosine interaction.		1974	4448180
nature of photochemical reactions in chromatophores of chromatium d. ii. quantum yield of photooxidation of cytochromes in chromatium chromatophores.		1974	4451654
[isolation of pigment-lipoprotein complexes from purple photosynthesizing bacteria by the method of preparative polyacrylamide gel electrophoresis].		1974	4453209
determination of the applied oxidation-reduction potential required for substrate reduction by chromatium nitrogenase.		1974	4455254
mössbauer effect in the high-potential iron-sulphur protein from chromatium. evidence for the state of the iron atoms.	1. the previous mössbauer work on chromatium high-potential iron-sulphur protein by moss et al. (1968) and evans et al. (1970) was extended to high applied magnetic fields. 2. measurements of the reduced protein confirm that it is non-magnetic. 3. spectra of the oxidized protein in applied magnetic fields clearly indicate that some iron atoms have a positive hyperfine field, which is evidence for antiferromagnetic coupling. 4. the spectra can be interpreted in terms of two types of iron atom wit ...	1974	4463936
[composition of nonconjugated pteridines in phototrophic bacteria].		1974	4208903
orthophosphate requirement for the formation of phosphoenolpyruvate from pyruvate by enzyme preparations from photosynthetic bacteria.	the formation of phosphoenolpyruvate from pyruvate and adenosine 5'-triphosphate by enzymes from photosynthetic bacteria required inorganic phosphate, thus indicating that these organisms utilize pyruvate, orthophosphate dikinase rather than phosphoenolpyruvate synthase in photosynthesis.	1974	4212219
one-step isolation of microbial ribulose-1,5-diphosphate carboxylase.		1974	4215394
correlation between the level of vitamin-b12-dependent methionine synthetase and intracellular concentration of vitamin b12 in some bacteria.		1974	4215653
properties of adenosinetriphosphatase in chromatophores and in coupling factor from the photosynthetic bacteria chromatium strain d.		1974	4275963
different pathways for fructose and glucose utilization in rhodopseudomonas capsulata and demonstration of 1-phosphofructokinase in phototrophic bacteria.		1974	4277436
the function of cytochrome c.		1974	4363927
magnetic studies on the changes in the iron environment in chromatium ferricytochrome c'.		1974	4364843
photoconversions of bacteriochlorophylls and cytochromes in chromatium chromatophores and cells under reducing conditions.		1974	4365134
synthetic analogs of the active sites of iron-sulfur proteins. 8. some electronic properties of (fe4s4(sr)4)3-, analogs of reduced bacterial ferredoxins.		1974	4365892
identification of ubiquinone as the secondary electron acceptor in the photosynthetic apparatus of chromatium vinosum.		1974	4366890
8 alpha-substituted flavins of biological importance.		1974	4369457
reaction center bacteriochlorophyll triplet states: redox potential dependence and kinetics.		1974	4370313
[initial pathways of pyruvate metabolism in phototrophic bacteria].		1974	4374642
the covalently bound flavin of chromatium cytochrome c552. 1. evidence for cysteine thiohemiacetal at the 8 alpha position.		1974	4375038
photosynthetic reaction centers and primary photochemical reactions.		1974	4376245
mössbauer effect in the 'super-reduced' form of the high-potential iron-sulphur protein from chromatium.	mössbauer-effect studies of the super-reduced form of chromatium high-potential iron-sulphur protein indicate that the iron atoms are in a similar valency state to those in reduced ferredoxin from clostridium pasteurianum, with possibly some inequivalence between the iron atoms within the four-iron centre. mössbauer spectroscopy also shows magnetic differences between the four-iron centres in the two proteins.	1974	4376953
the detection and characterization by electron-paramagnetic-resonance spectroscopy of iron-sulphur proteins and other electron-transport components in chromatophores from the purple bacterium chromatium.	low-temperature e.p.r. (electron-paramagnetic-resonance) spectroscopy was used to detect electron-transport components in chromatium chromatophores with e.p.r. signals in the g=2.00 region. high-potential iron protein (e(m8.0)=+325mv, where e(m8.0) is the midpoint potential at ph8) and a second component (g=1.90, e(m8.0)=+285mv) are oxidized in illuminated chromatophores. two iron-sulphur proteins (g=1.94) with e(m8.0)=-290mv and e(m8.0)=-50mv are present. one (e(m8.0)=-50mv) is reduced on illum ...	1974	4362737
electron transfer between biological molecules by thermally activated tunneling.	a theory of electron transfer between two fixed sites by tunneling is developed. vibronic coupling in the individual molecules produces an activation energy to transfer at high temperatures, and temperature-independent tunneling (when energetically allowed) at low temperature. the model is compared with known results on electron transfer in chromatium and in rhodopseudomonas spheroides. it quantitatively interprets these results, with parameters whose scale is verified by comparison with optical ...	1974	16592178
isotope fractionation in photosynthetic bacteria during carbon dioxide assimilation.	the delta (pdb) (13)c values have been determined for the cellular constituents and metabolic intermediates of autotrophically grown chromatium vinosum. the isotopic composition of the hco(3) (-) in the medium and the carbon isotopic composition of the bacterial cells change with the growth of the culture. the delta (pdb) (13)c value of the hco(3) (-) in the media changes from an initial value of -6.6 per thousand to +8.1 per thousand after 10 days of bacterial growth and the delta (pdb) (13)c v ...	1975	16659105
nh---s hydrogen bonds in peptococcus aerogenes ferredoxin, clostridium pasteurianum rubredoxin, and chromatium high potential iron protein.	results from refinement of the crystal structures of p. aerogenes ferredoxin and c. pasteurianum rubredoxin determined by x-ray diffraction show that there are 15-18 nh---s bonds in the former and six in the latter with lengths in the range 3.1-3.9 a. earlier tritium exchange experiments are consistent with the presence of these hydrogen bonds in the ferredoxin structure and show that more peptide hydrogen atoms are available for exchange in apoferredoxin than in intact ferredoxin. four types of ...	1975	1061073
photoinduced reduction of nad(p) in the cells of green sulfur bacteria.	the spectrum of a photoinduced increase in luminescence of the cells of the gree sulphur bacterium chlorobium limicola f. thiosulfatophilum, within the range of 400 to 520 nm, was found to correspond to the spectrum of luminescence of nadh in the protein-bound form. photoinduced reduction of nad(p) in green bacteria, contrary to purple bacteria, is not susceptible to the action of p-chlorocarbonylcyanide phenlhydrazone which uncouples photophosphorylation. therefore, in chlorobium limicola f. th ...	1975	2843
the nitrogen-fixing complex of bacteria.		1975	164247
the iron electron-nuclear double resonance (endor) of 4-fe clusters in iron-sulfur proteins from chromatium and clostridium pasteurianum.	iron electron-nuclear double resonance (endor) measurements were made of the 4-fe clusters in oxidized chromatium high-potential iron-sulfur protein, dithionite-reduced high-potential iron-sulfur protein in 80% dimethylsulphoxide, fully reduced clostridium pasteurianum ferredoxin in aqueous solution and in 80% dimethylsulfoxide. the hyperfine couplings determined show that: i) the electron distribution in each case is nearly symmetric; ii) there are two types of iron in oxidized high potential i ...	1975	164903
ribulose-5-phosphate kinase from chromatium.		1975	166272
immunological comparison of ferredoxins.		1975	166874
nature of photochemical reactions in chromatophores of chromatium d. iii. heterogeneity of the photosynthetic units.	the effect of isooctane extraction on photooxidation of c-type cytochromes was investigated in chromatium chromatophores. photooxidation of cytochrome c-555 was not affected by isooctane-extraction was abolished by thorough extraction of ubiquinone-7, but the quantum yield of the cytochrome photooxidation remained unchanged until 90% of the total ubiquinone was extracted. the photooxidation of cytochrome c-552 was recovered by the addition of ubiquinone-7 but not by menaquinone. a dark incubatio ...	1975	167850
evolution of photosystems of photosynthetic organisms.	it is generally accepted that two photosystems function successively in photosynthetic electron transport chain of plants and algae. the interaction of these photosystems results in the enhancement of photosynthesis. it was suggested that only one photosystem is present in purple bacteria, the most primitive photosynthetic organisms. the functioning of this photosystem is accompanied by absorption changes at 890 nm. recently new spectral changes were found in chramatium chromatophores under redu ...	1975	168538
[primary processes in energy transfer of photosynthesis (author's transl)].		1975	169548
high and low reduction potential 4fe-4s clusters in azotobacter vinelandii (4fe-4s) 2ferredoxin i. influence of the polypeptide on the reduction potentials.	azotobacter vinelandii (4fe-4s)2 ferredoxin i (fd i) is an electron transfer protein with mr equals 14,500 and eo equals -420 mv. it exhibits and epr signal of g equals 2.01 in its isolated form. this resonance is almost identical with the signal that originates from a "super-oxidized" state of the 4fe-4s cluster of potassium ferricyanide-treated clostridium ferredoxin. a cluster that exhibits this epr signal at g equals 2.01 is in the same formal oxidation state as the cluster in oxidized chrom ...	1975	170272
magnetic studies of the four-iron high-potential, non-heme protein from chromatium vinosum.	extensive epr studies on high-potential, iron-sulfur protein from chromatium vinosum indicate that the singular spectrum of this four-iron, non-heme protein consists of a superposition of three distinct signals; namely, two principal signals of equal weight, one reflecting axial and the other rhombic symmetry, and a third nearly isotropic minority component. in addition, magnetic susceptibility experiments on two oxidation states of the protein from 4.2 to approx. 260 degrees k indicate antiferr ...	1975	170982
[enzymes of carbohydrate metabolism in phototrophic bacteria].	purple sulphur bacteria (chromatium minutissimum, ectothiorhodospira shaposhnikovii, thiocapsa roseopersicina), non-sulphur bacteria (rhodopseudomonas palustris rh. viridis), and green sulphur bacteria (chlorobium limicola f. thiosulfatophillum) contain all enzymes of the fructose diphosphate pathway of carbohydrate transformation, and also glucose-6-phosphate dehydrogenase. the activity of fructose diphosphate aldolase, triose phosphate dehydrogenase, and glucose-6-phosphate dehydrogenase incre ...	1975	125844
proceedings: properties of adenosine triphosphatase in photosynthetic organisms.		1975	128539
further studies on the subunit structure of chromatium ribulose-1,5-phosphate carboxylase.	upon alkali exposure chromatium ribulose-1,5-bisphosphate carboxylase dissociates into constituent subunits, a catalytic oligomer of the larger subunit, a8, and monomeric form of the small subunit b. by sedimentation equilibrium molecular weights of the native enzyme and the catalytic oligomer produced by an alkali treatment were estimated to be 5.11 x 10 5 and 4.29 x 10 5, respectively. to provide information on reversibility of the dissociation by determining whether the enzymically inactive s ...	1975	234018
epr studies of protein state transitions in chromatium ferricytochrome c'.	recent magnetic studies have shown that in the ph range 1 to 11 the bacterial heme protein ferricytochrome c' can undergo reversible transitions between various pure high-spin and quantum mechanically mixed (intermediate and high)-spin protein states. the epr data presented here extend the recent work to high alkaline ph and show that above ph 11.6 reversible transitions occur between various pure high-spin and pure low-spin protein states. the new data and the previous magnetic studies of the p ...	1975	234758
the primary photochemical reaction to bacterial photosynthesis.		1975	235329
the reaction of euglena gracilis cytochrome c-552 with nonphysio-logical oxidants and reductants.		1975	237478
purification and properties of the glutathione reductase of chromatium vinosum.	the chromatium vinosum glutathione reductase [nad(p)h: glutathione disulfide oxidoreductase, ec 1.6.4.2] was purified to apparent homogeneity. the enzyme was found to require reduced nicotinamide adenine dinucleotide (nadh) as a reductant and to be specific for oxidized glutathione (gssg). the polypeptide molecular weight in sodium dodecyl sulfate was found to be 52,000. incubation of enzyme with nadh in the absence of gssg resulted in a significant loss in activity. the enzyme was stimulated by ...	1975	237878
the acid-base properties and kinetics of dissolution of the fe4s4 cores of chromatin ferredoxin and high potential iron protein.		1975	238529
structural and catalytic properties of hydrogenase from chromatium.	the enzyme hydrogenase, from the photosynthetic bacterium chromatium, was purified to homogeneity after solubilization of the particulate enzyme with deoxycholate. the purification procedure included ammonium sulfate fractionation, treatment with manganous phosphate gel, heating at 63 degrees, deae-cellulose chromatography, and isoelectric focusing. the last step gave two active enzyme fractions with isoelectric points of 4.2 and 4.4. it was shown that the two fractions were different forms of t ...	1975	238560
the role of sulfhydryl groups in the ribulose- 1,5-bisphosphate carboxylase and oxygenase reactions.		1975	241298
primary reactions in photosynthesis.		1975	814555
a morphological study of anaerobic bacteria from the hypolimnia of two michigan lakes.	dense populations of anaerobic bacteria were found sequentially layered below the thermocline in two eutrophic lakes in southwest michigan. phase and electron microscopy of whole cells and thin sections were used to reveal the in situ morphology of the dominant members of the community. the predominant chlorophyll-containing bacteria were identified on the basis of their morphology to be members of the genera pelodictyon, prosthecochloris, clathrochloris, chlorochromatium, pelochromatium, thiope ...	1975	1090350
the structure of anaerobic bacterial communities in the hypolimnia of several michigan lakes.	the structure of bacterial communities, the distribution of sulfide and oxygen, bacteriochlorophyll concentrations, and the temperature profile were determined for the anaerobic hypolimnia of two lakes in southern michigan. information from these studies, plus qualitative observations of two other lakes and two ponds over a 4-year period were used to correlate the spatial distribution of the populations, cell size, arrangement of photosynthetic vesicles or lamellae, presence of gas vacuoles or ...	1975	1090351
multiple-variant design for the enrichment of photosynthetic bacterial populations.	a design for the simultaneous variation of acetate, sulfide, and sulfate concentrations in 11 related media is described. selectivity of these media by a direct enumeration technique in solid culture was compared with that for enrichment in liquid culture. variation of nutritional parameters resulted in the selection of rhodospirillaceae at initial enrichment concentrations of 0.1 g or less of na2s-9 h2o per litre and chromatiaceae at 0.1 to 1.0 g of g of na2s-9 h2o per litre. the survival of ...	1975	1097075
cytochrome b and photosynthetic sulfur bacteria.	chromatophores isolated from the purple sulfur bacterium chromatium and the green sulfur bacterium chlorobium exhibit absorbance changes in the cytochrome alpha-band region consistent with the presence of a b-type cytochrome. cytochrome content determined by reduced minus oxidized difference spectra and by heme photochemically active bacteriochlorophyll (reaction-center bacteriochlorophyll). the b-type cytochrome in chromatium has an alpha-band maximum at 560 nm and a midpoint oxidation-reductio ...	1975	1125222
a large photoreactive particle from chromatium vinosum chromatophores.	large photoreactive particles from chromatium vinosum are obtained pure and in high yield by using a mixture of detergents at high ionic strength to dissociate the chromatophore membrane. the particles contain all of the secondary electron acceptor of the chromatophores and about half of the cytochrome. their content of ubiquinone is greatly enridhed as compared with chromatophores. th individual particles have an estimated molecular weight of between 650,000 and 810,000. gel electrophoresis ...	1975	1125294
crystallographic structure refinement of chromatium high potential iron protein at two angstroms resolution.	the structure of chromatium high potential iron protein (hipip) has been refined by semiautomatic fo-fc (observed minus calculated structure amplitude fourier methods to a convential r index, r=sum of the absolute value of fo-fc divided by the sum of fo, of 24.7% for a model in which bond distances and angles are constrained to standard values. bond length and angle constraints were applied only intermittenly during the computations. at a late stage of the refinement, atomic parameters for only ...	1975	1141211
[effect of temperature on the phototransformation of purple sulfur bacteria bacteriochlorophylls and isolated chromatophores].	photobleaching of p890 was shown to be independent of temperature within the range of +20 to -160 degrees c in purple sulphur bacteria and isolated chromatophores under oxidative conditions; therefore changes in the absorption at 890 nm are due to the primary photoact. no changes were detected in the absorption at 850 nm upon a slight decrease of temperature, which suggested the absorption at 850 nm upon a slight decrease of temperature, which suggested the conformation nature of these changes. ...	1975	1160647
x-ray photoelectron spectra of iron-sulphur proteins.	the x-ray photoelectron spectra of the 2p, 3s and 3p levels of iron in oxidized clostridium pasteurianum ferredoxin indicate that the eight iron atoms in the molecule are indistinguishable. their magnetic state is indicated both by core polarization splitting of the 3s electrons, and by "shake-up' satellites on the 2p lines. similar satellites are observed in the 2p lines of reduced chromatium high-potential iron-sulphur proteins and oxidized spinach ferredoxin, indicating that there too the iro ...	1975	1180907
isolation and partial characterization of the photochemical reaction center of chromatium vinosum (strain d).		1975	1187805
[ribosomal proteins of the photosynthesizing bacterium chromatium vinosum].		1975	1212922
primary structure of a high potential iron-sulfur protein from the purple non-sulfur photosynthetic bacterium rhodopseudomonas gelatinosa.	the third amino acid sequence of a high potential iron-sulfur protein, that of the non-sulfur purple photosynthetic bacterium rhodopseudomonas gelatinosa, has been determined. it consists of a single polypeptide chain of 74 amino acid residues, which is slightly smaller than the high potential iron-sulfur proteins from the sulfur purple bacteria chromatium vinosum (85 residues) and thiocapsa pfennigii (81 residues). the sequence of the gelatinosa protein is similar to the c. vinosum and t. pfenn ...	1976	1244346
new experimental approach to the estimation of rate of electron transfer from the primary to secondary acceptors in the photosynthetic electron transport chain of purple bacteria.	a method for calculating the rate constant (ka1a2) for the oxidation of the primary electron acceptor (a1) by the secondary one (a2) in the photosynthetic electron transport chain of purple bacteria is proposed. the method is based on the analysis of the dark recovery kinetics of reaction centre bacteriochlorophyll (p) following its oxidation by a short single laser pulse at a high oxidation-reduction potential of the medium. it is shown that in ectothiorhodospira shaposhnikovii there is little ...	1976	816385