Electrochemistry of R. palustris Azul during phototrophic growth

2020 ◽  
Vol 355 ◽  
pp. 136757
Author(s):  
Aisha E. Guardia ◽  
María V. Beligni ◽  
Néstor Cortéz ◽  
Juan Pablo Busalmen
Keyword(s):  
Phototrophic Growth

scholarly journals Genes essential for phototrophic growth by a purple alphaproteobacterium

2017 ◽  
Vol 19 (9) ◽  
pp. 3567-3578 ◽  
Author(s):  
Jianming Yang ◽  
Liang Yin ◽  
Faith H. Lessner ◽  
Ernesto S. Nakayasu ◽  
Samuel H. Payne ◽  
...  
Keyword(s):  
Phototrophic Growth

Model-supported phototrophic growth studies with Scenedesmus obtusiusculus in a flat-plate photobioreactor

2016 ◽  
Vol 114 (2) ◽  
pp. 308-320 ◽  
Author(s):  
Anja Pia Koller ◽  
Hannes Löwe ◽  
Verena Schmid ◽  
Sabine Mundt ◽  
Dirk Weuster-Botz
Keyword(s):  
Flat Plate ◽  
Growth Studies ◽  
Flat Plate Photobioreactor ◽  
Phototrophic Growth

scholarly journals Regulation of nap Gene Expression and Periplasmic Nitrate Reductase Activity in the Phototrophic Bacterium Rhodobacter sphaeroides DSM158

2002 ◽  
Vol 184 (6) ◽  
pp. 1693-1702 ◽  
Author(s):  
Mónica Gavira ◽  
M. Dolores Roldán ◽  
Francisco Castillo ◽  
Conrado Moreno-Vivián
Keyword(s):  
Rhodobacter Sphaeroides ◽  
Nitrate Reduction ◽  
Reductase Activity ◽  
Enzyme Activation ◽  
Nitrite Accumulation ◽  
Northern Blots ◽  
Reverse Transcription Pcr ◽  
Phototrophic Growth ◽  
Very High

ABSTRACT Bacterial periplasmic nitrate reductases (Nap) can play different physiological roles and are expressed under different conditions depending on the organism. Rhodobacter sphaeroides DSM158 has a Nap system, encoded by the napKEFDABC gene cluster, but nitrite formed is not further reduced because this strain lacks nitrite reductase. Nap activity increases in the presence of nitrate and oxygen but is unaffected by ammonium. Reverse transcription-PCR and Northern blots demonstrated that the napKEFDABC genes constitute an operon transcribed as a single 5.5-kb product. Northern blots and nap-lacZ fusions revealed that nap expression is threefold higher under aerobic conditions but is regulated by neither nitrate nor ammonium, although it is weakly induced by nitrite. On the other hand, nitrate but not nitrite causes a rapid enzyme activation, explaining the higher Nap activity found in nitrate-grown cells. Translational nap′-′lacZ fusions reveal that the napK and napD genes are not efficiently translated, probably due to mRNA secondary structures occluding the translation initiation sites of these genes. Neither butyrate nor caproate increases nap expression, although cells growing phototrophically on these reduced substrates show a very high Nap activity in vivo (nitrite accumulation is sevenfold higher than in medium with malate). Phototrophic growth on butyrate or caproate medium is severely reduced in the NapA− mutants. Taken together, these results indicate that nitrate reduction in R. sphaeroides is mainly regulated at the level of enzyme activity by both nitrate and electron supply and confirm that the Nap system is involved in redox balancing using nitrate as an ancillary oxidant to dissipate excess reductant.

scholarly journals Catellibacterium nectariphilum gen. nov., sp. nov., which requires a diffusible compound from a strain related to the genus Sphingomonas for vigorous growth

2004 ◽  
Vol 54 (3) ◽  
pp. 955-959 ◽  
Author(s):  
Yasuhiro Tanaka ◽  
Satoshi Hanada ◽  
Akira Manome ◽  
Takayasu Tsuchida ◽  
Ryuichiro Kurane ◽  
...  
Keyword(s):  
Optimal Growth ◽  
Cellular Fatty Acid ◽  
Phenotypic Traits ◽  
Rrna Gene ◽  
Aerobic Bacterium ◽  
Respiratory Quinone ◽  
Vigorous Growth ◽  
Major Respiratory Quinone ◽  
Ubiquinone 10 ◽  
Phototrophic Growth

A bacterial strain, designated AST4T, was isolated from activated sludge. The bacterium did not show significant growth on nutrient broth, but growth was clearly stimulated by addition of supernatant from other bacterial cultures. Culture filtrate of a strain related to the genus Sphingomonas in particular increased the cell yield and growth rate of strain AST4T. Phylogenetic analysis based on the 16S rRNA gene sequences showed that strain AST4T is located within the ‘Rhodobacter group’ in the α-3 subclass of Proteobacteria, but is clearly distant from related genera in this group such as Paracoccus, Rhodobacter and Rhodovulum. Strain AST4T is a Gram-negative, non-motile, rod-shaped (0·6–0·8×1·3–2·0 μm) and aerobic bacterium. It was not able to reduce nitrate to nitrite or N2. No phototrophic growth was observed. Optimal growth occurred at 30 °C and pH 6·5–7·5. The dominant cellular fatty acid in the isolate was C18 : 1 cis11. Ubiquinone-10 was the major respiratory quinone. The G+C content was 64·5 mol% (by HPLC). Based on the phylogenetic and phenotypic traits, the name Catellibacterium nectariphilum gen. nov., sp. nov. is proposed for this isolate; the type strain is AST4T (=NBRC 100046T=JCM 11959T=DSM 15620T).

Sign in / Sign up

Export Citation Format

Share Document