Recent Posts

Breaking Water-wise Photosynthesis

Boxall et al. explore the effects of silencing phosphoenolpyruvate carboxylase in a Crassulacean acid metabolism species. Plant Cell https://doi.org/10.1105/tpc.19.00481 By Susie Boxall and James Hartwell Background: Severe droughts and high temperatures are becoming more frequent due to climate…

Structural basis of unidirectional energy transfer in Porphyridium purpureum phycobilisome (Nature)

Cyanobacteria and red algae employ phycobilisomes (PBSs) as light-harvesting systems to adapt to fluctuating environments. PBSs are composed of phycobiliproteins, linker proteins and chromophores. Ma et al. used cryo-EM to determine the 2.82 Å structure of  the very large (14.7-megadalton, 706 protein…

Embryonic photosynthesis affects post-germination plant growth (Plant Physiol.)

Angiosperm seeds develop within maternal tissues, yet in some species including Arabidopsis the developing embryos carry out photosynthesis. In Arabidopsis, this is transitory, and the embryonic chloroplasts lose chlorophyll and dedifferentiate into eoplasts as the seed matures. Sela et al. set out to…

The photosystem factory in chloroplasts

Sun et al. reveal the subcellular organization of photosystem biogenesis in Chlamydomonas. Plant Cell https://doi.org/10.1105/tpc.19.00263 by Melissa Valente-Paterno, Yi Sun and William Zerges. Department of Biology, Concordia University.  Background: Cells localize intracellular processes to…

Special Issue: New perspectives on crassulacean acid metabolism biology

Crassulacean acid metabolism (CAM) is a water-conserving strategy in which stomata open at night and carbon is stored until daytime photosynthesis provides the energy to fix it. This special issue of the Journal of Experimental Botany, edited by Hultine, Cushman, and Williams, brings together a set of…

Subdivision of light signaling networks contributes to partitioning of C4 photosynthesis (Plant Physiol)

Some plants such as Zea mays partition different components of the photosynthetic pathway in mesophyll cells (MC) and bundle sheath cells (BSC) in a process known as two-cell C4 photosynthesis. For example, light-harvesting reactions carried out by photosystem I and II (PSI and PSII) occur only in the…

Synthetic biogenesis of chromoplasts from leaf chloroplasts (bioRxiv)

Chromoplasts are a type of plastid, usually found in fruits and flowers, that can accumulate large amounts of carotenoids including beta-carotene (pro-vitamin A). It has been proposed that increasing chromoplast formation could be a way to enhance human consumption of vitamin A. In a new report, Llorente…

On the origin of oxygenic photosynthesis and cyanobacteria (New Phytol)

Photosynthesis occurs in several ways, only one of which releases oxygen as a product. As oxygen-breathing organisms, we are totally dependent on oxygenic photosynthesis, which is restricted to cyanobacteria and green plant plastids. In this review, Sánchez‐Baracaldo and Cardona examine how recent…

A novel hypothesis for the role of photosynthetic physiology in shaping macroevolutionary patterns (Plant Physiol)

In the 450 million(ish) years since plants acquired the ability to live on land, they have caused dramatic changes in the concentrations of atmospheric CO2 and O2 levels. As an example, due to tremendous increases in photosynthesis, CO2 levels dropped and O2 levels rose dramatically in the late Paleozoic…