In the photosynthetic bacterium Rhodobacter capsulatus, the enzyme DNA gyrase has been implicated in the expression of genes for anaerobic metabolic processes such as nitrogen fixation and photosynthesis. To assess the involvement of supercoiling in anaerobic gene expression, we have developed an assay to detect in vivo changes in superhelicity of small regions of the bacterial chromosome. Our ...

BACKGROUND AND AIMS In crops other than sugarcane there is good evidence that the size and activity of carbon sinks influence source activity via sugar-related regulation of the enzymes of photosynthesis, an effect that is partly mediated through coarse regulation of gene expression. METHODS In the current study, leaf shading treatments were used to perturb the source-sink balance in 12-month...

Gastrodia pubilabiata is a nonphotosynthetic and mycoheterotrophic orchid belonging to subfamily Epidendroideae. Compared other typical angiosperm species, the plastome of G. dramatically reduced in size only 30,698 base pairs (bp). This reduction has led loss most photosynthesis-related genes some housekeeping plastome, which now contains 19 protein coding genes, three tRNAs, rRNAs. In contras...

To understand the network architecture of miRNA mediated regulations at the genomic and functional levels of rice, we have made an unambiguous annotation of the experimentally verified miRNAs, predicted their targets and the possible biological functions they can affect. Some functions, namely translational and protein modifications and photosynthesis are targeted by higher percentage of miRNA....

We have previously constructed the physical map of a cyanobacterium, Synechoystis sp. strain PCC6803 on the basis of restriction and linking clone analysis. Since a total of 82 genes and gene clusters have been isolated from this strain, most of which are involved in oxygenic photosynthesis, portions of their sequences were amplified by the PCR method and assigned on the physical map of the gen...

A DNA sequence has been obtained for a 35.6-kb genomic segment from Heliobacillus mobilis that contains a major cluster of photosynthesis genes. A total of 30 ORFs were identified, 20 of which encode enzymes for bacteriochlorophyll and carotenoid biosynthesis, reaction-center (RC) apoprotein, and cytochromes for cyclic electron transport. Donor side electron-transfer components to the RC includ...

The sea slug Elysia chlorotica acquires plastids by ingestion of its algal food source Vaucheria litorea. Organelles are sequestered in the mollusc's digestive epithelium, where they photosynthesize for months in the absence of algal nucleocytoplasm. This is perplexing because plastid metabolism depends on the nuclear genome for >90% of the needed proteins. Two possible explanations for the per...

The light spectral composition acting through a set of photoreceptors, such as cryptochromes and phytochromes, plays an important role in maintaining sustainable photosynthesis. An impact cryptochrome 1 deficiency additions green (GL) against the background red (RL) blue (BL) (different ratios RL:BL:GL) on activity photosynthetic apparatus, content pigments, pro-/antioxidant balance, expression...

C(4) photosynthesis outperforms the ancestral C(3) state in a wide range of natural and agro-ecosystems by affording higher water-use and nitrogen-use efficiencies. It therefore represents a prime target for engineering novel, high-yielding crops by introducing the trait into C(3) backgrounds. However, the genetic architecture of C(4) photosynthesis remains largely unknown. To define the diverg...

PpsR is a major regulator of photosynthesis gene expression among all characterized purple photosynthetic bacteria. This transcription regulator has been extensively characterized in Rhodobacter (Rba.) capsulatus and Rba. sphaeroides which are members of the α-proteobacteria lineage. In this study, we have investigated the biochemical properties and mutational effects of a ppsR deletion strain ...