Structure-Guided Mutations in the Terminal Organelle Protein MG491 Cause Major Motility and Morphologic Alterations on Mycoplasma genitalium.
PLoS Pathogens 12(4):e1005533 (2016)
The emergent human pathogen Mycoplasma genitalium, with one of the smallest genomes among cells capable of growing in axenic cultures, presents a flask-shaped morphology due to a protrusion of the cell membrane, known as the terminal organelle, that is involved in cell adhesion and motility and ...
Correction: Selective photoregulation of the activity of glycogen synthase and glycogen phosphorylase, two key enzymes in glycogen metabolism.
Organic & Biomolecular Chemistry 13(39):10072 (2015)
Correction for 'Selective photoregulation of the activity of glycogen synthase and glycogen phosphorylase, two key enzymes in glycogen metabolism' by Mireia Díaz-Lobo, et al., Org. Biomol. Chem., 2015, 13, 7282-7288.
Eukaryotic Catalase-Peroxidase: The Role of the Trp-Tyr-Met Adduct in Protein Stability, Substrate Accessibility, and Catalysis of Hydrogen Peroxide Dismutation.
Biochemistry (Washington) 54(35):5425 (2015)
Recently, it was demonstrated that bifunctional catalase-peroxidases (KatGs) are found not only in archaea and bacteria but also in lower eukaryotes. Structural studies and preliminary biochemical data of the secreted KatG from the rice pathogen Magnaporthe grisea (MagKatG2) suggested both simil...
Selective photoregulation of the activity of glycogen synthase and glycogen phosphorylase, two key enzymes in glycogen metabolism.
Organic & Biomolecular Chemistry 13(26):7282 (2015)
Glycogen is a polymer of α-1,4- and α-1,6-linked glucose units that provides a readily available source of energy in living organisms. Glycogen synthase (GS) and glycogen phosphorylase (GP) are the two enzymes that control, respectively, the synthesis and degradation of this polysaccharide and c...
A major determinant for gliding motility in Mycoplasma genitalium: the interaction between the terminal organelle proteins MG200 and MG491.
Journal of Biological Chemistry 290(3):1699 (2015)
Several mycoplasmas, such as the emergent human pathogen Mycoplasma genitalium, developed a complex polar structure, known as the terminal organelle (TO), responsible for a new type of cellular motility, which is involved in a variety of cell functions: cell division, adherence to host cells, an...
Vibrational entropy of a protein: large differences between distinct conformations.
Journal of Chemical Theory and Computation 11(1):351 (2015)
In this article, it is investigated whether vibrational entropy (VE) is an important contribution to the free energy of globular proteins at ambient conditions. VE represents the major configurational-entropy contribution of these proteins. By definition, it is an average of the configurational ...
Calcineurin Undergoes a Conformational Switch Evoked via Peptidyl-Prolyl Isomerization.
PLoS ONE 10(8):e0134569 (2015)
A limited repertoire of PPP family of serine/threonine phosphatases with a highly conserved catalytic domain acts on thousands of protein targets to orchestrate myriad central biological roles. A major structural reorganization of human calcineurin, a ubiquitous Ser/Thr PPP regulated by calcium ...
Structure of human carbamoyl phosphate synthetase: deciphering the on/off switch of human ureagenesis.
Scientific reports 5:16950 (2015)
Human carbamoyl phosphate synthetase (CPS1), a 1500-residue multidomain enzyme, catalyzes the first step of ammonia detoxification to urea requiring N-acetyl-L-glutamate (NAG) as essential activator to prevent ammonia/amino acids depletion. Here we present the crystal structures of CPS1 in the a...
An ionizable active-site tryptophan imparts catalase activity to a peroxidase core.
Journal of the American Chemical Society 136(20):7249 (2014)
Catalase peroxidases (KatG's) are bifunctional heme proteins that can disproportionate hydrogen peroxide (catalatic reaction) despite their structural dissimilarity with monofunctional catalases. Using X-ray crystallography and QM/MM calculations, we demonstrate that the catalatic reaction of Ka...
Binding of the antitubercular pro-drug isoniazid in the heme access channel of catalase-peroxidase (KatG). A combined structural and metadynamics investigation.
Journal of Physical Chemistry B 118(11):2924 (2014)
Isonicotinic acid hydrazide (isoniazid or INH) is a front line antitubercular pro-drug that is converted to its active form, isonicotinyl-NAD, by the bacterial catalase-peroxidase KatG. Understanding the role of KatG in the INH activation process has been hampered by a lack of knowledge of the a...
Structure and interaction with phospholipids of a prokaryotic lipoxygenase from Pseudomonas aeruginosa.
FASEB Journal 27(12):4811 (2013)
Lipoxygenases (LOXs), which are essential in eukaryotes, have no confirmed function in prokaryotes that are devoid of polyunsaturated fatty acids. The structure of a secretable LOX from Pseudomonas aeruginosa (Pa_LOX), the first available from a prokaryote, presents significant differences with ...
Spectroscopic and kinetic investigation of the reactions of peroxyacetic acid with Burkholderia pseudomallei catalase-peroxidase, KatG.
Biochemistry (Washington) 52(41):7271 (2013)
Catalase-peroxidases or KatGs can utilize organic peroxyacids and peroxides instead of hydrogen peroxide to generate the high-valent ferryl-oxo intermediates involved in the catalase and peroxidase reactions. In the absence of peroxidatic one-electron donors, the ferryl intermediates generated w...
Structural asymmetry and disulfide bridges among subunits modulate the activity of human malonyl-CoA decarboxylase.
Journal of Biological Chemistry 288(17):11907 (2013)
Decarboxylation of malonyl-CoA to acetyl-CoA by malonyl-CoA decarboxylase (MCD; EC 188.8.131.52) is an essential facet in the regulation of fatty acid metabolism. The structure of human peroxisomal MCD reveals a molecular tetramer that is best described as a dimer of structural heterodimers, in which...
Structure of Pisum sativum Rubisco with bound ribulose 1,5-bisphosphate.
Acta Crystallographica Section F 69(Pt 1):10 (2013)
The first structure of a ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) from a pulse crop is reported. Rubisco was purified from Pisum sativum (garden pea) and diffraction-quality crystals were obtained by hanging-drop vapour diffusion in the presence of the substrate ribulose 1,5-bis...
X-ray crystallography of viruses.
Sub-Cellular Biochemistry 68:117 (2013)
For about 30 years X-ray crystallography has been by far the most powerful approach for determining virus structures at close to atomic resolutions. Information provided by these studies has deeply and extensively enriched and shaped our vision of the virus world. In turn, the ever increasing co...
Structure of glycerol-3-phosphate dehydrogenase (GPD1) from Saccharomyces cerevisiae at 2.45 Å resolution.
Acta Crystallographica Section F 68(Pt 11):1279 (2012)
The interconversion of glycerol 3-phosphate and dihydroxyacetone phosphate by glycerol-3-phosphate dehydrogenases provides a link between carbohydrate and lipid metabolism and provides Saccharomyces cerevisiae with protection against osmotic and anoxic stress. The first structure of a glycerol-3...
The EAGR box structure: a motif involved in mycoplasma motility.
Molecular Microbiology 86(2):382 (2012)
Mycoplasma genitalium is an emerging human pathogen with the smallest genome found among self-replicating organisms. M. genitalium presents a complex cytoskeleton with a differentiated protrusion known as the terminal organelle. This polar structure plays a central role in functions essential fo...
Influence of main channel structure on H(2)O(2) access to the heme cavity of catalase KatE of Escherichia coli.
Archives of Biochemistry and Biophysics 526(1):54 (2012)
The main channel for H(2)O(2) access to the heme cavity in large subunit catalases is twice as long as in small subunit catalases and is divided into two distinct parts. Like small subunit catalases, the 15Å of the channel adjacent to the heme has a predominantly hydrophobic surface with only we...
Thirty years of heme catalases structural biology.
Archives of Biochemistry and Biophysics 525(2):102 (2012)
About thirty years ago the crystal structures of the heme catalases from Penicillium vitale (PVC) and, a few months later, from bovine liver (BLC) were published. Both enzymes were compact tetrameric molecules with subunits that, despite their size differences and the large phylogenetic separati...
High conformational stability of secreted eukaryotic catalase-peroxidases: answers from first crystal structure and unfolding studies.
Journal of Biological Chemistry 287(38):32254 (2012)
Catalase-peroxidases (KatGs) are bifunctional heme enzymes widely spread in archaea, bacteria, and lower eukaryotes. Here we present the first crystal structure (1.55 Å resolution) of an eukaryotic KatG, the extracellular or secreted enzyme from the phytopathogenic fungus Magnaporthe grisea. The...