Publications

short-chain dehydrogenases/reductases (sdrs) in cyanobacteria.	the short-chain dehydrogenases/reductases (sdrs) represent a large superfamily of enzymes, most of which are nad(h)- or nadp(h)-dependent oxidoreductases. they display a wide substrate spectrum, including steroids, alcohols, sugars, aromatic compounds and xenobiotics. based on characteristic sequence motifs, the sdrs are subdivided into two main ("classical" and "extended") and three smaller ("divergent", "intermediate", "complex") families. despite low residue identities in pairwise comparison, ...	2012	22251568
unique properties of eukaryote-type actin and profilin horizontally transferred to cyanobacteria.	a eukaryote-type actin and its binding protein profilin encoded on a genomic island in the cyanobacterium microcystis aeruginosa pcc 7806 co-localize to form a hollow, spherical enclosure occupying a considerable intracellular space as shown by in vivo fluorescence microscopy. biochemical and biophysical characterization reveals key differences between these proteins and their eukaryotic homologs. small-angle x-ray scattering shows that the actin assembles into elongated, filamentous polymers wh ...	2012	22253827
the photophysics of the orange carotenoid protein, a light-powered molecular switch.	to cope with deleterious effects of excess illumination, photosynthetic organisms have developed photoprotective mechanisms that dissipate the absorbed excess energy as heat from the antenna system. in cyanobacteria, a crucial step in the process is the activation, by blue-green light, of a soluble protein, known as orange carotenoid protein (ocp) which binds the carotenoid 3'-hydroxyechinenone as its only pigment. while the spectroscopic properties of the inactive form of ocp have been describ ...	2012	22257008
arsenic biomethylation by photosynthetic organisms.	arsenic (as) is a ubiquitous element that is widespread in the environment and causes numerous health problems. biomethylation of as has implications for its mobility and toxicity. photosynthetic organisms may play a significant role in as geochemical cycling by methylating it to different as species, but little is known about the mechanisms of methylation. methylated as species have been found in many photosynthetic organisms, and several arsenite s-adenosylmethionine (sam) methyltransferases h ...	2012	22257759
identification of a new nanornase in bartonella.	in escherichia coli, only one essential oligoribonuclease (orn) can degrade oligoribonucleotides of five residues and shorter in length (nanorna). in bacillus subtilis, nrna and nrnb, which do not have any sequence similarity with orn, have been identified as functional analogs of orn. sequence comparisons did not allow identifying orn, nrna, or nrnb homologues in the genomes of the chlamydia/cyanobacteria and alphaproteobacteria family members. screening a genomic library from bartonella birtle ...	2012	22262096
cyanobacteria: impacts of climate change on occurrence, toxicity and water quality management.		2011	22265251
net light-induced oxygen evolution in photosystem i deletion mutants of the cyanobacterium synechocystis sp. pcc 6803.	oxygenic photosynthesis in cyanobacteria, algae, and plants requires photosystem ii (psii) to extract electrons from h(2)o and depends on photosystem i (psi) to reduce nadp(+). here we demonstrate that mixotrophically-grown mutants of the cyanobacterium synechocystis sp. pcc 6803 that lack psi (δpsi) are capable of net light-induced o(2) evolution in vivo. the net light-induced o(2) evolution requires glucose and can be sustained for more than 30min. utilizing electron transport inhibitors and c ...	2012	22266340