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Title: Electron partitioning in soluble organic products by wild-type and modified Synechocystis sp. PCC 6803

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Journal Article: Publisher's Accepted Manuscript
Journal Name:
Biomass and Bioenergy
Additional Journal Information:
Journal Volume: 90; Journal Issue: C; Related Information: CHORUS Timestamp: 2017-10-03 22:14:16; Journal ID: ISSN 0961-9534
Country of Publication:
United Kingdom

Citation Formats

Nguyen, Binh T., and Rittmann, Bruce E. Electron partitioning in soluble organic products by wild-type and modified Synechocystis sp. PCC 6803. United Kingdom: N. p., 2016. Web. doi:10.1016/j.biombioe.2016.04.016.
Nguyen, Binh T., & Rittmann, Bruce E. Electron partitioning in soluble organic products by wild-type and modified Synechocystis sp. PCC 6803. United Kingdom. doi:10.1016/j.biombioe.2016.04.016.
Nguyen, Binh T., and Rittmann, Bruce E. Fri . "Electron partitioning in soluble organic products by wild-type and modified Synechocystis sp. PCC 6803". United Kingdom. doi:10.1016/j.biombioe.2016.04.016.
title = {Electron partitioning in soluble organic products by wild-type and modified Synechocystis sp. PCC 6803},
author = {Nguyen, Binh T. and Rittmann, Bruce E.},
abstractNote = {},
doi = {10.1016/j.biombioe.2016.04.016},
journal = {Biomass and Bioenergy},
number = C,
volume = 90,
place = {United Kingdom},
year = {Fri Jul 01 00:00:00 EDT 2016},
month = {Fri Jul 01 00:00:00 EDT 2016}

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Free Publicly Available Full Text
Publisher's Version of Record at 10.1016/j.biombioe.2016.04.016

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Cited by: 4works
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  • The authors present here a simple and rapid method which allows relatively large quantities of oxygen-evolving photosystem II- (PS-II-) enriched particles to be obtained from wild-type and mutants of the cyanobacterium Synechocystis 6803. This method is based on that of Burnap et al. but is modified so that the whole preparation, from cells to PS-II particles, is achieved in 10 h and involves only one purification step. The purified preparation exhibits a 5-6-fold increase of O{sub 2}-evolution activity on a chlorophyll basis over the thylakoids. The ratio of PS-I to PS-II is about 0.14:1 in the preparation. The secondary quinonemore » electron acceptor, Q{sub B}, is present in this preparation as demonstrated by thermoluminescence studies. These PS-II particles are well-suited to spectroscopic studies as demonstrated by the range of EPR signals arising from components of PS-II that are easily detectable. Among the EPR signals presented are those from a formal S{sub 3}-state, attributed to an oxidized amino acid interacting magnetically with the Mn complex in Ca{sup 2+}-deficient PS-II particles, and from S{sub 2} modified by the replacement of Ca{sup 2+} by Sr{sup 2+}. Neither of these signals has been previously reported in cyanobacteria. Their detection under these conditions indicates a similar lesion caused by Ca{sup 2+} depletion in both plants and cyanobacteria. The protocol has been applied to mutants which have site-specific changes in PS-II. Data are presented on mutants have changes on the electron donor (Y160F) and electron acceptor (G215W) side of the D{sub 2} polypeptide.« less
  • Hydrolysis of plant biomass generates a mixture of simple sugars that is particularly rich in glucose and xylose. Fermentation of the released sugars emits CO 2 as byproduct due to metabolic inefficiencies. Therefore, the ability of a microbe to simultaneously convert biomass sugars and photosynthetically fix CO 2 into target products is very desirable. In this work, the cyanobacterium, Synechocystis 6803, was engineered to grow on xylose in addition to glucose. Both the xylA (xylose isomerase) and xylB (xylulokinase) genes from Escherichia coli were required to confer xylose utilization, but a xylose-specific transporter was not required. Introducing xylAB into anmore » ethylene-producing strain increased the rate of ethylene production in the presence of xylose. Additionally, introduction of xylAB into a glycogen-synthesis mutant enhanced production of keto acids. Moreover, isotopic tracer studies found that nearly half of the carbon in the excreted keto acids was derived from the engineered xylose metabolism, while the remainder was derived from CO 2 fixation.« less
  • Cited by 14
  • Among a wide range of potential selective agents examined, sodium p-hydroxymercuribenzoate successfully enriched for mutants of Synechocystis sp. strains PCC 6714 and 6803 defective in photosynthesis. When both photosystems I and II were operating, viability of wild-type cells decreased to between 5 x 10/sup -5/ and 1 x 10/sup -6/ after 5 h of incubation with 500 p-hydroxymercuribenzoate (strain 6714), and after 8 h with 200 (strain 6803). Between 0.1 and 0.5% of the survivors were stable mutants defective in different steps of photosynthesis. The compound was not mutagenic. It was less toxic to cells grown chemoheterotrophically inmore » the dark or photoheterotrophically in the presence of 3-(3,4-dichlorophenyl-1,1-dimethylurea. p-Hydroxymercuribenzoate therefore killed only cells which were performing photosynthesis at high rates, thereby specif« less
  • In the cyanobacterium Synechocystis sp. strain PCC 6803 (Synechocystis 6803) {delta}-aminolevulinic acid (ALA), the sole precursor for the synthesis of the porphyrin rings of heme and chlorophyll, is formed from glutamate activated by acylation to tRNA{sup Glu}. We report here that Synechocystis 6803 possesses a single tRNA{sup Glu} gene which was transcribed as monomeric precursor tRNA and matured into the two tRNA{sup Glu} species. They differed in the extent of modification of the first anticodon base, 5-methylaminomethyl-2-thiouridine. The two tRNA species had equivalent capacities to stimulate the tRNA-dependent formation of ALA in Synechocystis 6803 and to provide glutamate for proteinmore » biosynthesis in an Escherichia coli-derived translation system. These results are in support of a dual role of tRNA{sup Glu}. The levels of tRNA{sup Glu} were examined by Northern (RNA) blot analysis of cellular RNA and by aminoacylation assays in cultures of Synechocystis 6803 in which the amount of chlorophyll synthesized was modulated over a 10-fold range by various illumination regimens or by the addition of inhibitors of chlorophyll and ALA biosynthesis. In these cultures, the level of tRNA{sup Glu} was always a constant fraction of the total tRNA population, suggesting that tRNA{sup Glu} and chlorophyll levels are regulated independently. In addition, the tRNA{sup Glu} was always fully aminoacylated in vivo.« less