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Acta Crystallogr Sect F Struct Biol Cryst Commun 2013 Dec 30;69(Pt 12):1440-2. Epub 2013 Nov 30.

Department of Biotechnology, Indian Institute of Technology Guwahati, Guwahati 781 039, India.

The modular carbohydrate-active enzyme belonging to glycoside hydrolase family 30 (GH30) from Clostridium thermocellum (CtXynGH30) is a cellulosomal protein which plays an important role in plant cell-wall degradation. The full-length CtXynGH30 contains an N-terminal catalytic module (Xyn30A) followed by a family 6 carbohydrate-binding module (CBM6) and a dockerin at the C-terminus. The recombinant protein has a molecular mass of 45 kDa. Read More

Acta Crystallogr Sect F Struct Biol Cryst Commun 2013 Dec 29;69(Pt 12):1436-9. Epub 2013 Nov 29.

State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai 200433, People's Republic of China.

The Escherichia coli cyclic AMP receptor protein (CRP) is a prokaryotic global transcription activator protein that controls the expression of many different genes. Wild-type CRP can bind to special DNA sequences in the presence of cAMP. The substitution of Asp53 by His results in the CRP* phenotype, which does not require exogenous cAMP. Read More

Acta Crystallogr Sect F Struct Biol Cryst Commun 2013 Dec 29;69(Pt 12):1431-5. Epub 2013 Nov 29.

Department of Environmental Protection, Consejo Superior de Investigaciones Científicas, Estación Experimental del Zaidín, Calle Profesor Albareda 1, E-18008 Granada, Spain.

Pseudomonas aeruginosa is an opportunistic pathogen and one of the major model organisms for the study of chemotaxis. The bacterium harbours 26 genes encoding chemoreceptors, most of which have not been annotated with a function. The paralogous chemoreceptors PctA and PctB (Pseudomonas chemotactic transducer A and B) were found to mediate chemotaxis towards L-amino acids. Read More

Acta Crystallogr Sect F Struct Biol Cryst Commun 2013 Dec 29;69(Pt 12):1425-30. Epub 2013 Nov 29.

Structural Bases of Genome Integrity Group, Structural Biology and Biocomputing Programme, Spanish National Cancer Research Centre (CNIO), Melchor Fernández Almagro 3, 28029 Madrid, Spain.

Aspartate transcarbamoylase (ATCase) catalyzes the synthesis of N-carbamoyl-L-aspartate from carbamoyl phosphate and aspartate in the second step of the de novo biosynthesis of pyrimidines. In prokaryotes, the first three activities of the pathway, namely carbamoyl phosphate synthetase (CPSase), ATCase and dihydroorotase (DHOase), are encoded as distinct proteins that function independently or in noncovalent association. In animals, CPSase, ATCase and DHOase are part of a 243 kDa multifunctional polypeptide named CAD. Read More

Acta Crystallogr Sect F Struct Biol Cryst Commun 2013 Dec 29;69(Pt 12):1422-4. Epub 2013 Nov 29.

Molecular Biophysics Unit, Indian Institute of Science, Bangalore 560 012, India.

The last enzyme in the arginine-biosynthesis pathway, argininosuccinate lyase, from Mycobacterium tuberculosis has been cloned, expressed, purified and crystallized, and preliminary X-ray studies have been carried out on the crystals. The His-tagged tetrameric enzyme with a subunit molecular weight of 50.9 kDa crystallized with two tetramers in the asymmetric unit of the orthorhombic unit cell, space group P2(1)2(1)2(1). Read More

Acta Crystallogr Sect F Struct Biol Cryst Commun 2013 Dec 29;69(Pt 12):1418-21. Epub 2013 Nov 29.

Department of Chemistry, York University, 4700 Keele Street, Toronto, ON M3J 1P3, Canada.

The response-regulatory protein LytR belongs to a family of transcription factors involved in the regulation of important virulence factors in pathogenic bacteria. The protein consists of a receiver domain and an effector domain, which play an important role in controlled cell death and lysis. The LytR receiver domain (LytR(N)) has been overexpressed, purified and crystallized using the sitting-drop and hanging-drop vapour-diffusion methods. Read More

Acta Crystallogr Sect F Struct Biol Cryst Commun 2013 Dec 29;69(Pt 12):1415-7. Epub 2013 Nov 29.

Institut für Biochemie, Universität Greifswald, Felix-Hausdorff-Strasse 4, D-17489 Greifswald, Germany.

The (R)-selective amine transaminase from Aspergillus fumigatus was expressed in Escherichia coli and purified to homogeneity. Bright yellow crystals appeared while storing the concentrated solution in the refrigerator and belonged to space group C222(1). X-ray diffraction data were collected to 1. Read More

Acta Crystallogr Sect F Struct Biol Cryst Commun 2013 Dec 29;69(Pt 12):1411-4. Epub 2013 Nov 29.

Biomolecular Research Unit, National Institute of Agrobiological Sciences, Tsukuba, Ibaraki 305-0856, Japan.

Tm-1, an inhibitor protein of Tomato mosaic virus RNA replication, contains two conserved domains: an uncharacterized domain at its N-terminus and a TIM-barrel-like domain at its C-terminus. The N-terminal domain of Tm-1 has an inhibitory activity and its three-dimensional structure has not been determined. Here, the crystallization and preliminary X-ray diffraction of the N-terminal domain of Tm-1 are reported. Read More

Acta Crystallogr Sect F Struct Biol Cryst Commun 2013 Dec 29;69(Pt 12):1405-10. Epub 2013 Nov 29.

Institute of Human Virology, University of Maryland School of Medicine, Baltimore, MD 21201, USA.

Endoglycosidase S (EndoS) is an enzyme secreted by Streptococcus pyogenes that specifically hydrolyzes the β-1,4-di-N-acetylchitobiose core glycan on immunoglobulin G (IgG) antibodies. One of the most common human pathogens and the cause of group A streptococcal infections, S. pyogenes secretes EndoS in order to evade the host immune system by rendering IgG effector mechanisms dysfunctional. Read More

Acta Crystallogr Sect F Struct Biol Cryst Commun 2013 Dec 29;69(Pt 12):1401-4. Epub 2013 Nov 29.

Advanced Centre for Treatment, Research and Education in Cancer, Kharghar, Navi Mumbai 410 210, India.

The BRCA1 holoenzyme complex plays an important role in DNA damage repair. ABRAXAS is a newly discovered component of this complex and its C-terminal region directly binds to the BRCA1 BRCT domain. Single crystals of the BRCA1 BRCT-ABRAXAS complex grown by co-crystallization belonged to space group P4(1)2(1)2, with unit-cell parameters a = b = 187. Read More

Acta Crystallogr Sect F Struct Biol Cryst Commun 2013 Dec 29;69(Pt 12):1397-400. Epub 2013 Nov 29.

Department of Material and Biological Chemistry, Graduate School of Science and Engineering, Yamagata University, 1-4-12 Kojirakawa, Yamagata 990-8560, Japan.

Class B β-lactamases are known as metallo-β-lactamases (MBLs) and they hydrolyze most β-lactams, including carbapenems. IMP-18, an MBL cloned from Pseudomonas aeruginosa, was overexpressed, purified and crystallized by vapour diffusion for X-ray crystallographic analysis. Preliminary X-ray analysis showed that the crystal diffracted to 2. Read More

Acta Crystallogr Sect F Struct Biol Cryst Commun 2013 Dec 29;69(Pt 12):1393-6. Epub 2013 Nov 29.

Departamento de Estructura de Macromoléculas, Centro Nacional de Biotecnología (CNB-CSIC), Calle Darwin 3, 28049 Madrid, Spain.

CHAP(K) is the N-terminal cysteine, histidine-dependent amidohydrolase/peptidase domain (CHAP domain) of the Staphylococcus aureus bacteriophage K endolysin LysK. It is formed from the first 165 residues of LysK and functions by cleaving specific peptidoglycan peptide bonds, causing bacterial lysis. CHAP(K) can lyse S. Read More

Acta Crystallogr Sect F Struct Biol Cryst Commun 2013 Dec 29;69(Pt 12):1389-92. Epub 2013 Nov 29.

Department of Chemistry, University of Turku, Joint Biotechnology Laboratory, BioCity, Tykistökatu 6A, 20520 Turku, Finland.

The outbreak of Shiga toxin-producing Escherichia coli O104:H4 infection in Germany in 2011 was associated with significant mortality and morbidity owing to the progressive development of haemolytic-uraemic syndrome. The outbreak strain emerged recently as a result of horizontal transfer events leading to the acquisition of a number of virulence factors. Among them, aggregative adherence fimbriae type I (AAF/I) are considered to be particularly important since they are involved in the initial attachment of bacteria to the intestinal mucosa. Read More

Acta Crystallogr Sect F Struct Biol Cryst Commun 2013 Dec 29;69(Pt 12):1384-8. Epub 2013 Nov 29.

Biochemistry and Molecular Biology, Penn State University, University Park, PA 16802, USA.

One way that bacteria regulate the transcription of specific genes to adapt to environmental challenges is to use different σ factors that direct the RNA polymerase holoenzyme to distinct promoters. Unlike σ(70) RNA polymerase (RNAP), σ(54) RNAP is unable to initiate transcription without an activator: enhancer-binding protein (EBP). All EBPs contain one ATPase domain that belongs to the family of ATPases associated with various cellular activities (AAA+ ATPases). Read More

Acta Crystallogr Sect F Struct Biol Cryst Commun 2013 Dec 29;69(Pt 12):1380-3. Epub 2013 Nov 29.

Krebs Institute for Biomolecular Research, Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2TN, England.

Coccidiosis in chickens is caused by the apicomplexan parasite Eimeria tenella and is thought to involve a role for a superfamily of more than 20 cysteine-rich surface antigen glycoproteins (SAGs) in host-parasite interactions. A representative member of the family, SAG19, has been overexpressed in Escherichia coli, purified and crystallized by the hanging-drop method of vapour diffusion using ammonium sulfate as the precipitant. Crystals of SAG19 diffracted to beyond 1. Read More

Acta Crystallogr Sect F Struct Biol Cryst Commun 2013 Dec 29;69(Pt 12):1374-9. Epub 2013 Nov 29.

Departamento de Estructura de Macromoléculas, Centro Nacional de Biotecnología (CNB-CSIC), Calle Darwin 3, 28049 Madrid, Spain.

Adenovirus fibre proteins play an important role in determining viral tropism. The C-terminal domain of the fibre protein from snake adenovirus type 1, a member of the Atadenovirus genus, has been expressed, purified and crystallized. Crystals were obtained belonging to space groups P2(1)2(1)2(1) (two different forms), I2(1)3 and F23. Read More

Acta Crystallogr Sect F Struct Biol Cryst Commun 2013 Dec 29;69(Pt 12):1371-3. Epub 2013 Nov 29.

Department of General Dentistry, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology, Shanghai 200011, People's Republic of China.

LKB1, a tumour suppressor, plays key roles in cell polarity, cell growth and energy metabolism. 14-3-3 proteins bind to LKB1 and suppress its functions. A chimera containing 14-3-3ζ and its binding region in LKB1 was constructed and the chimeric protein LKB1-14-4-3ζ was purified and crystallized. Read More

Acta Crystallogr Sect F Struct Biol Cryst Commun 2013 Dec 29;69(Pt 12):1368-70. Epub 2013 Nov 29.

Picobiology Institute, Graduate School of Life Science, University of Hyogo, 3-2-1 Kouto, Kamigori Akoh, Hyogo 678-1297, Japan.

Mitochondrial F-ATP synthase produces the majority of ATP for cellular functions requiring free energy. The structural basis for proton motive force-driven rotational catalysis of ATP formation in the holoenzyme remains to be determined. Here, the purification and two-dimensional crystallization of bovine heart mitochondrial F-ATP synthase are reported. Read More

Acta Crystallogr Sect F Struct Biol Cryst Commun 2013 Dec 28;69(Pt 12):1363-7. Epub 2013 Nov 28.

Departamento de Estructura de Macromoléculas, Centro Nacional de Biotecnología (CNB-CSIC), Calle Darwin 3, 28049 Madrid, Spain.

Tails of bacteriophage T5 (a member of the Siphoviridae family) were studied by electron microscopy. For the distal parts of the L-shaped tail fibres, which are involved in host cell receptor binding, a low-resolution volume was calculated. Several C-terminal fragments of the fibre were expressed and purified. Read More

Acta Crystallogr Sect F Struct Biol Cryst Commun 2013 Dec 28;69(Pt 12):1360-2. Epub 2013 Nov 28.

Department of Advanced Bioscience, Kinki University, 3327-204 Nakamachi, Nara 631-8505, Japan.

The catalytic mechanism of family GH19 chitinases is not well understood owing to insufficient information regarding the three-dimensional structures of enzyme-substrate complexes. Here, the crystallization and preliminary X-ray diffraction analysis of a selenomethionine-labelled active-site mutant of `loopless' family GH19 chitinase from the moss Bryum coronatum in complex with chitotetraose, (GlcNAc)4, are reported. The crystals were grown using the vapour-diffusion method. Read More

Acta Crystallogr Sect F Struct Biol Cryst Commun 2013 Dec 28;69(Pt 12):1357-9. Epub 2013 Nov 28.

Frontier Research Center for Applied Atomic Sciences, Ibaraki University, 162-1 Shirakata, Tokai, Naka, Ibaraki 319-1106, Japan.

Peptidylarginine deiminase (PAD) catalyzes the post-translational conversion of peptidylarginine to peptidylcitrulline in the presence of calcium ions. Among the five known human PAD isozymes (PAD1-4 and PAD6), PAD1 exhibits the broadest substrate specificity. Crystals of PAD1 obtained using polyethylene glycol 3350 as a precipitant diffracted to 3. Read More

Acta Crystallogr Sect F Struct Biol Cryst Commun 2013 Dec 28;69(Pt 12):1354-6. Epub 2013 Nov 28.

Structural Biology Laboratory, School of Biological Sciences and Maurice Wilkins Centre for Molecular Biodiscovery, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand.

In Mycobacterium tuberculosis, the protein MbtN (Rv1346) catalyzes the formation of a double bond in the fatty-acyl moiety of the siderophore mycobactin, which is used by this organism to acquire essential iron. MbtN is homologous to acyl-CoA dehydrogenases, whose general role is to catalyze the α,β-dehydrogenation of fatty-acyl-CoA conjugates. Mycobactins, however, contain a long unsaturated fatty-acid chain with an unusual cis double bond conjugated to the carbonyl group of the mycobactin core. Read More

Acta Crystallogr Sect F Struct Biol Cryst Commun 2013 Dec 28;69(Pt 12):1349-53. Epub 2013 Nov 28.

Structural and Molecular Microbiology, VIB Department of Structural Biology, VIB, Pleinlaan 2, 1050 Brussels, Belgium.

Gram-negative bacteria have eight known protein secretion systems. The type-VIII secretion system, also known as the curli biosynthesis system, is responsible for the formation of aggregative fibres known in Escherichia coli as curli. Curli are extracellular proteinaceous fibres primarily involved in bacterial biofilm formation and attachment to nonbiotic surfaces. Read More

Acta Crystallogr Sect F Struct Biol Cryst Commun 2013 Dec 28;69(Pt 12):1344-8. Epub 2013 Nov 28.

Teijin Institute for Bio-medical Research, Teijin Pharma Ltd, 4-3-2 Asahigaoka, Hino-shi, Tokyo 191-8512, Japan.

Mitogen-activated protein kinase-activated protein kinase 2 (MK2 or MAPKAP-K2), a serine/threonine kinase from the p38 mitogen-activated protein kinase signalling pathway, plays an important role in the production of TNF-α and other cytokines. In a previous report, it was shown that MK2 in complex with the selective inhibitor TEI-I01800 adopts an α-helical glycine-rich loop that is induced by the stable nonplanar conformer of TEI-I01800. To understand the mechanism of the structural change, the structure of MK2 bound to TEI-L03090, which lacks the key substituent found in TEI-I01800, was determined. Read More

Acta Crystallogr Sect F Struct Biol Cryst Commun 2013 Dec 28;69(Pt 12):1339-43. Epub 2013 Nov 28.

Division of Biological Chemistry and Drug Discovery, College of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland.

Siah1 is an E3 ubiquitin ligase that contributes to proteasome-mediated degradation of multiple targets in key cellular processes and which shows promise as a therapeutic target in oncology. Structures of a truncated Siah1 bound to peptide-based inhibitors have been reported. Here, new crystallization conditions have allowed the determination of a construct encompassing dual zinc-finger subdomains and substrate-binding domains at significantly higher resolution. Read More

Acta Crystallogr Sect F Struct Biol Cryst Commun 2013 Dec 28;69(Pt 12):1335-8. Epub 2013 Nov 28.

BioSciences Center, National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, CO 80401, USA.

Here, a 1.82 Å resolution X-ray structure of a glycoside hydrolase family 74 (GH74) enzyme from Acidothermus cellulolyticus is reported. The resulting structure was refined to an R factor of 0. Read More

Acta Crystallogr Sect F Struct Biol Cryst Commun 2013 Dec 28;69(Pt 12):1328-34. Epub 2013 Nov 28.

Department of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA.

Poxvirus uracil DNA glycosylases are the most diverse members of the family I uracil DNA glycosylases (UNGs). The crystal structure of the uracil complex of Vaccinia virus uracil DNA glycosylase (D4) was determined at 2.03 Å resolution. Read More

Acta Crystallogr Sect F Struct Biol Cryst Commun 2013 Dec 28;69(Pt 12):1322-7. Epub 2013 Nov 28.

Institut de Recherche Interdisciplinaire, IRI USR 3078 CNRS-Université Lille Nord de France, Parc CNRS de la Haute Borne, 50 Avenue de Halley, 59658 Villeneuve d'Ascq, France.

Haemophilus influenzae HxuA is a cell-surface protein with haem-haemopexin binding activity which is key to haem acquisition from haemopexin and thus is one of the potential sources of haem for this microorganism. HxuA is secreted by its specific transporter HxuB. HxuA/HxuB belongs to the so-called two-partner secretion systems (TPSs) that are characterized by a conserved N-terminal domain in the secreted protein which is essential for secretion. Read More

Acta Crystallogr Sect F Struct Biol Cryst Commun 2013 Dec 28;69(Pt 12):1316-21. Epub 2013 Nov 28.

Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL 60637, USA.

A key role in signal transduction and dimerization mediated by Per-Arnt-Sim (PAS) domains is played by α-helical linkers that flank the structurally similar α/β cores of these domains. However, crystal-packing forces and the different construct lengths and sequences of the PAS domains influence the final length and orientation of the linkers relative to the core and create uncertainty in the exact mechanism of the linker function. Thus, structural characterization and comparison of the linkers within isolated PAS-domain constructs and/or full-length PAS-containing proteins is important for clarification of the mechanism. Read More

Acta Crystallogr Sect F Struct Biol Cryst Commun 2013 Dec 30;69(Pt 12):1315. Epub 2013 Nov 30.

Helmholtz-Zentrum Berlin für Materialien und Energie, Macromolecular Crystallography (HZB-MX), Albert-Einstein-Strasse 15, D-12489 Berlin, Germany.