Search results for "CHLOROPLAST"
showing 5 items of 145 documents
Phylogeny, biogeography and evolution of Triglochin L. (Juncaginaceae) – Morphological diversification is linked to habitat shifts rather than to gen…
2015
A species-level phylogeny is presented for Triglochin, the largest genus of Juncaginaceae (Alismatales) comprising about 30 species of annual and perennial herbs. Triglochin has an almost cosmopolitan distribution with Australia as centre of species diversity. Trans-Atlantic and trans-African disjunctions exist in the genus. Phylogenetic analyses were conducted based on molecular data obtained from nuclear (ITS, internal transcribed spacer) and chloroplast sequence data (psbA-trnH spacer, matK gene). Based on the phylogeny of the group divergence times were estimated and ancestral distribution areas reconstructed. Our data confirm the monophyly of Triglochin and resolve relationships betwee…
Redox modulation of Rubisco conformation and activity through its cysteine residues
2008
Treatment of purified Rubisco with agents that specifically oxidize cysteine-thiol groups causes catalytic inactivation and increased proteolytic sensitivity of the enzyme. It has been suggested that these redox properties may sustain a mechanism of regulating Rubisco activity and turnover during senescence or stress. Current research efforts are addressing the structural basis of the redox modulation of Rubisco and the identification of critical cysteines. Redox shifts result in Rubisco conformational changes as revealed by the alteration of its proteolytic fragmentation pattern upon oxidation. In particular, the augmented susceptibility of Rubisco to proteases is due to increased exposure…
Data from: Rumbling orchids: how to assess divergent evolution between chloroplast endosymbionts and the nuclear host
2015
Phylogenetic relationships inferred from multilocus organellar and nuclear DNA data are often difficult to resolve because of evolutionary conflicts among gene trees. However, conflicting or “outlier” associations (i.e., linked pairs of “operational terminal units” in two phylogenies) among these data sets often provide valuable information on evolutionary processes such as chloroplast capture following hybridization, incomplete lineage sorting, and horizontal gene transfer. Statistical tools that to date have been used in cophylogenetic studies only also have the potential to test for the degree of topological congruence between organellar and nuclear data sets and reliably detect outlier …
Dynamin-Like Proteins Are Potentially Involved in Membrane Dynamics within Chloroplasts and Cyanobacteria
2017
Dynamin-like proteins (DLPs) are a family of membrane-active proteins with low sequence identity. The proteins operate in different organelles in eukaryotic cells, where they trigger vesicle formation, membrane fusion, or organelle division. As discussed here, representatives of this protein family have also been identified in chloroplasts and DLPs are very common in cyanobacteria. Since cyanobacteria and chloroplasts, an organelle of bacterial origin, have similar internal membrane systems, we suggest that DLPs are involved in membrane dynamics in cyanobacteria and chloroplasts. Here, we discuss the features and activities of DLPs with a focus on their potential presence and activity in ch…