Publications by authors named "Chia-Shin Yang"

18 Publications

  • Page 1 of 1

Crystal structure and functional implication of a bacterial cyclic AMP-AMP-GMP synthetase.

Nucleic Acids Res 2021 May;49(8):4725-4737

Institute of New Drug Development, China Medical University, Taichung 406, Taiwan.

Mammalian cyclic GMP-AMP synthase (cGAS) and its homologue dinucleotide cyclase in Vibrio cholerae (VcDncV) produce cyclic dinucleotides (CDNs) that participate in the defense against viral infection. Recently, scores of new cGAS/DncV-like nucleotidyltransferases (CD-NTases) were discovered, which produce various CDNs and cyclic trinucleotides (CTNs) as second messengers. Here, we present the crystal structures of EcCdnD, a CD-NTase from Enterobacter cloacae that produces cyclic AMP-AMP-GMP, in its apo-form and in complex with ATP, ADP and AMPcPP, an ATP analogue. Despite the similar overall architecture, the protein shows significant structural variations from other CD-NTases. Adjacent to the donor substrate, another nucleotide is bound to the acceptor binding site by a non-productive mode. Isothermal titration calorimetry results also suggest the presence of two ATP binding sites. GTP alone does not bind to EcCdnD, which however binds to pppApG, a possible intermediate. The enzyme is active on ATP or a mixture of ATP and GTP, and the best metal cofactor is Mg2+. The conserved residues Asp69 and Asp71 are essential for catalysis, as indicated by the loss of activity in the mutants. Based on structural analysis and comparison with VcDncV and RNA polymerase, a tentative catalytic pathway for the CTN-producing EcCdnD is proposed.
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http://dx.doi.org/10.1093/nar/gkab165DOI Listing
May 2021

Screening strategy of TMPRSS2 inhibitors by FRET-based enzymatic activity for TMPRSS2-based cancer and COVID-19 treatment.

Am J Cancer Res 2021 1;11(3):827-836. Epub 2021 Mar 1.

Institute of New Drug Development, China Medical University Taichung, Taiwan.

Transmembrane serine protease (TMPRSS2) plays an oncogenic role in prostate cancer as the fusion gene with ERG, and has also been demonstrated to be essential for the cellular entry of severe acute respiratory syndrome coronaviruses (SARS-CoV). Thus, targeting TMPRSS2 is a promising strategy for therapies against both prostate cancer and coronavirus infection. Although Nafamostat and Camostat have been identified as TMPRSS2 inhibitors, severe side effects such as cerebral hemorrhage, anaphylactoid reaction, and cardiac arrest shock greatly hamper their clinical use. Therefore, more potent and safer drugs against this serine protease should be further developed. In this study, we developed a fluorescence resonance energy transfer (FRET)-based platform for effectively screening of inhibitors against TMPRSS2 protease activity. The disruption of FRET between green and red fluorescent proteins conjugated with the substrate peptide, which corresponds to the cleavage site of SARS-CoV-2 Spike protein, was measured to determine the enzymatic activity of TMPRSS2. Through an initiate pilot screening with around 100 compounds, Flupirtine, a selective neuronal potassium channel opener, was identified as a potential TMPRSS2 inhibitor from an FDA-approved drug library by using this screening platform, and showed inhibitory effect on the TMPRSS-dependent infection of SARS-CoV-2 Spike-pseudotyped lentiviral particles. This study describes a platform proven effective for rapidly screening of TMPRSS2 inhibitors, and suggests that Flupirtine may be worthy of further consideration of repurposing to treat COVID-19 patients.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7994159PMC
March 2021

Tannic acid suppresses SARS-CoV-2 as a dual inhibitor of the viral main protease and the cellular TMPRSS2 protease.

Am J Cancer Res 2020 1;10(12):4538-4546. Epub 2020 Dec 1.

Graduate Institute of Biomedical Sciences, College of Medicine, China Medical University Taichung 40402, Taiwan.

The cell surface protein TMPRSS2 (transmembrane protease serine 2) is an androgen-responsive serine protease important for prostate cancer progression and therefore an attractive therapeutic target. Besides its role in tumor biology, TMPRSS2 is also a key player in cellular entry by the SARS-CoV viruses. The COVID-19 pandemic caused by the coronavirus SARS-CoV-2 has resulted in huge losses in socio-economy, culture, and human lives for which safe and effective cures are highly demanded. The main protease (M/3CL) of SARS-CoV-2 is a critical enzyme for viral propagation in host cells and, like TMPRSS2, has been exploited for treatment of the infectious disease. Numerous natural compounds abundant in common fruits have been suggested with anti-coronavirus infection in the previous outbreaks of SARS-CoV. Here we show that screening of these compounds identified tannic acid a potent inhibitor of both SARS-CoV-2 M and TMPRSS2. Molecular analysis demonstrated that tannic acid formed a thermodynamically stable complex with the two proteins at a K of 1.1 mM for M and 1.77 mM for TMPRSS2. Tannic acid inhibited the activities of the two proteases with an IC of 13.4 mM for M and 2.31 mM for TMPRSS2. M protein. Consistently, functional assays using the virus particles pseudotyped (Vpp) of SARS-CoV2-S demonstrated that tannic acid suppressed viral entry into cells. Thus, our results demonstrate that tannic acid has high potential of developing anti-COVID-19 therapeutics as a potent dual inhibitor of two independent enzymes essential for SARS-CoV-2 infection.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7783773PMC
December 2020

Crystal structure of the N-terminal domain of TagH reveals a potential drug targeting site.

Biochem Biophys Res Commun 2021 01 22;536:1-6. Epub 2020 Dec 22.

Institute of New Drug Development, China Medical University, Taichung, 406, Taiwan; Drug Development Center, Research Center for Cancer Biology and Center for Molecular Medicine, China Medical University, Taichung, 40402, Taiwan. Electronic address:

Bacterial wall teichoic acids (WTAs) are synthesized intracellularly and exported by a two-component transporter, TagGH, comprising the transmembrane and ATPase subunits TagG and TagH. Here the dimeric structure of the N-terminal domain of TagH (TagH-N) was solved by single-wavelength anomalous diffraction using a selenomethionine-containing crystal, which shows an ATP-binding cassette (ABC) architecture with RecA-like and helical subdomains. Besides significant structural differences from other ABC transporters, a prominent patch of positively charged surface is seen in the center of the TagH-N dimer, suggesting a potential binding site for the glycerol phosphate chain of WTA. The ATPase activity of TagH-N was inhibited by clodronate, a bisphosphonate, in a non-competitive manner, consistent with the proposed WTA-binding site for drug targeting.
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http://dx.doi.org/10.1016/j.bbrc.2020.12.028DOI Listing
January 2021

Structural basis of SARS-CoV-2 main protease inhibition by a broad-spectrum anti-coronaviral drug.

Am J Cancer Res 2020 1;10(8):2535-2545. Epub 2020 Aug 1.

Institute of New Drug Development, China Medical University Taichung 40402, Taiwan.

The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) or 2019 novel coronavirus (2019-nCoV), took tens of thousands of lives and caused tremendous economic losses. The main protease (M) of SARS-CoV-2 is a potential target for treatment of COVID-19 due to its critical role in maturation of viral proteins and subsequent viral replication. Conceptually and technically, targeting therapy against M is similar to target therapy to treat cancer. Previous studies show that GC376, a broad-spectrum dipeptidyl M inhibitor, efficiently blocks the proliferation of many animal and human coronaviruses including SARS-CoV, Middle East respiratory syndrome coronavirus (MERS-CoV), porcine epidemic diarrhea virus (PEDV), and feline infectious peritonitis virus (FIPV). Due to the conservation of structure and catalytic mechanism of coronavirus main protease, repurposition of GC376 against SARS-CoV-2 may be an effective way for the treatment of COVID-19 in humans. To validate this conjecture, the binding affinity and IC value of M with GC376 was determined by isothermal titration calorimetry (ITC) and fluorescence resonance energy transfer (FRET) assay, respectively. The results showed that GC376 binds to SARS-CoV-2 M tightly (K = 1.6 μM) and efficiently inhibit its proteolytic activity (IC = 0.89 μM). We also elucidate the high-resolution structure of dimeric SARS-CoV-2 M in complex with GC376. The cocrystal structure showed that GC376 and the catalytic Cys145 of M covalently linked through forming a hemithioacetal group and releasing a sulfonic acid group. Because GC376 is already known as a broad-spectrum antiviral medication and successfully used in animal, it will be a suitable candidate for anti-COVID-19 treatment.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7471349PMC
August 2020

The tetrameric structure of sialic acid-synthesizing UDP-GlcNAc 2-epimerase from : A comparative study with human GNE.

J Biol Chem 2018 06 15;293(26):10119-10127. Epub 2018 May 15.

the Department of Biotechnology, Hungkuang University, Taichung 433, Taiwan

Sialic acid presentation on the cell surface by some pathogenic strains of bacteria allows their escape from the host immune system. It is one of the major virulence factors. Bacterial biosynthesis of sialic acids starts with the conversion of UDP-GlcNAc to UDP and ManNAc by a hydrolyzing 2-epimerase. Here, we present the crystal structure of this enzyme, named NeuC, from The protein folds into two Rossmann-like domains and forms dimers and tetramers as does the epimerase part of the bifunctional UDP-GlcNAc 2-epimerase/ManNAc kinase (GNE). In contrast to human GNE, which showed only the closed conformation, the NeuC crystals contained both open and closed protomers in each dimer. Substrate soaking changed the space group from C222 to P222 In addition to UDP, an intermediate-like ligand was seen bound to the closed protomer. The UDP-binding mode in NeuC was similar to that in GNE, although a few side chains were rotated away. NeuC lacks the CMP-Neu5Ac-binding site for allosteric inhibition of GNE. However, the two enzymes as well as other NeuC homologues (but not SiaA from ) appear to be common in tetrameric organization. The revised two-base catalytic mechanism may involve His-125 (Glu-134 in GNE), as suggested by mutant activity analysis.
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http://dx.doi.org/10.1074/jbc.RA118.001971DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6028959PMC
June 2018

SH3-like motif-containing C-terminal domain of staphylococcal teichoic acid transporter suggests possible function.

Proteins 2016 09 8;84(9):1328-32. Epub 2016 Jun 8.

Department of Biotechnology, Hungkuang University, Taichung, Taiwan.

The negatively charged bacterial polysaccharides-wall teichoic acids (WTAs) are synthesized intracellularly and exported by a two-component transporter, TagGH, comprising a transmembrane subunit TagG and an ATPase subunit TagH. We determined the crystal structure of the C-terminal domain of TagH (TagH-C) to investigate its function. The structure shows an N-terminal SH3-like subdomain wrapped by a C-terminal subdomain with an anti-parallel β-sheet and an outer shell of α-helices. A stretch of positively charged surface across the subdomain interface is flanked by two negatively charged regions, suggesting a potential binding site for negatively charged polymers, such as WTAs or acidic peptide chains. Proteins 2016; 84:1328-1332. © 2016 Wiley Periodicals, Inc.
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http://dx.doi.org/10.1002/prot.25074DOI Listing
September 2016

Crystal structures of Staphylococcal SaeR reveal possible DNA-binding modes.

Biochem Biophys Res Commun 2016 06 3;474(4):686-690. Epub 2016 May 3.

Department of Biotechnology, Hungkuang University, No.1018, Sec. 6, Taiwan Boulevard, Shalu District, Taichung 43302, Taiwan. Electronic address:

Two-component system SaeRS of Staphylococcus regulates virulence factor expression through phosphorylation of the DNA-binding regulator SaeR by the sensor histidine kinase SaeS. Here crystal structures of the DNA-binding domain (DBD) of SaeR from two Staphylococcal species Staphylococcus epidermidis and Staphylococcus aureus were determined and showed similar folds. Analyzing the DNA binding activity of three mutants of SeSaeR, we observed that Thr217 is important in binding to the phosphate group of DNA and Trp219 may interact with the base pairs. Additionally, the tandem arrangement of DBD may represent a possible way for SaeR oligomerization on DNA.
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http://dx.doi.org/10.1016/j.bbrc.2016.05.009DOI Listing
June 2016

Mechanism and inhibition of human UDP-GlcNAc 2-epimerase, the key enzyme in sialic acid biosynthesis.

Sci Rep 2016 Mar 16;6:23274. Epub 2016 Mar 16.

Department of Biotechnology, Hungkuang University, Taichung, Taiwan.

The bifunctional enzyme UDP-GlcNAc 2-epimerase/ManNAc kinase (GNE) plays a key role in sialic acid production. It is different from the non-hydrolyzing enzymes for bacterial cell wall biosynthesis, and it is feed-back inhibited by the downstream product CMP-Neu5Ac. Here the complex crystal structure of the N-terminal epimerase part of human GNE shows a tetramer in which UDP binds to the active site and CMP-Neu5Ac binds to the dimer-dimer interface. The enzyme is locked in a tightly closed conformation. By comparing the UDP-binding modes of the non-hydrolyzing and hydrolyzing UDP-GlcNAc epimerases, we propose a possible explanation for the mechanistic difference. While the epimerization reactions of both enzymes are similar, Arg113 and Ser302 of GNE are likely involved in product hydrolysis. On the other hand, the CMP-Neu5Ac binding mode clearly elucidates why mutations in Arg263 and Arg266 can cause sialuria. Moreover, full-length modelling suggests a channel for ManNAc trafficking within the bifunctional enzyme.
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http://dx.doi.org/10.1038/srep23274DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4793188PMC
March 2016

Structure and mechanism of an antibiotics-synthesizing 3-hydroxykynurenine C-methyltransferase.

Sci Rep 2015 May 11;5:10100. Epub 2015 May 11.

Department of Biotechnology, Hungkuang University, Taichung, Taiwan.

Streptosporangium sibiricum SibL catalyzes the methyl transfer from S-adenosylmethionine (SAM) to 3-hydroxykynurenine (3-HK) to produce S-adenosylhomocysteine (SAH) and 3-hydroxy-4-methyl-kynurenine for sibiromycin biosynthesis. Here, we present the crystal structures of apo-form Ss-SibL, Ss-SibL/SAH binary complex and Ss-SibL/SAH/3-HK ternary complex. Ss-SibL is a homodimer. Each subunit comprises a helical N-terminal domain and a Rossmann-fold C-terminal domain. SAM (or SAH) binding alone results in domain movements, suggesting a two-step catalytic cycle. Analyses of the enzyme-ligand interactions and further mutant studies support a mechanism in which Tyr134 serves as the principal base in the transferase reaction of methyl group from SAM to 3-HK.
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http://dx.doi.org/10.1038/srep10100DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4426599PMC
May 2015

Crystal structure of Deinococcus radiodurans RecQ helicase catalytic core domain: the interdomain flexibility.

Biomed Res Int 2014 27;2014:342725. Epub 2014 Aug 27.

Department of Biotechnology, Hungkuang University, Taichung 433, Taiwan.

RecQ DNA helicases are key enzymes in the maintenance of genome integrity, and they have functions in DNA replication, recombination, and repair. In contrast to most RecQs, RecQ from Deinococcus radiodurans (DrRecQ) possesses an unusual domain architecture that is crucial for its remarkable ability to repair DNA. Here, we determined the crystal structures of the DrRecQ helicase catalytic core and its ADP-bound form, revealing interdomain flexibility in its first RecA-like and winged-helix (WH) domains. Additionally, the WH domain of DrRecQ is positioned in a different orientation from that of the E. coli RecQ (EcRecQ). These results suggest that the orientation of the protein during DNA-binding is significantly different when comparing DrRecQ and EcRecQ.
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http://dx.doi.org/10.1155/2014/342725DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4163472PMC
May 2016

Crystal structure of a conserved hypothetical protein MJ0927 from Methanocaldococcus jannaschii reveals a novel quaternary assembly in the Nif3 family.

Biomed Res Int 2014 28;2014:171263. Epub 2014 Aug 28.

Department of Biotechnology, Hungkuang University, Taichung 433, Taiwan.

A Nif3 family protein of Methanocaldococcus jannaschii, MJ0927, is highly conserved from bacteria to humans. Although several structures of bacterial Nif3 proteins are known, no structure representing archaeal Nif3 has yet been reported. The crystal structure of Methanocaldococcus jannaschii MJ0927 was determined at 2.47 Å resolution to understand the structural differences between the bacterial and archaeal Nif3 proteins. Intriguingly, MJ0927 is found to adopt an unusual assembly comprising a trimer of dimers that forms a cage-like architecture. Electrophoretic mobility-shift assays indicate that MJ0927 binds to both single-stranded and double-stranded DNA. Structural analysis of MJ0927 reveals a positively charged region that can potentially explain its DNA-binding capability. Taken together, these data suggest that MJ0927 adopts a novel quartenary architecture that could play various DNA-binding roles in Methanocaldococcus jannaschii.
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http://dx.doi.org/10.1155/2014/171263DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4163360PMC
May 2016

Crystal structures of the archaeal UDP-GlcNAc 2-epimerase from Methanocaldococcus jannaschii reveal a conformational change induced by UDP-GlcNAc.

Proteins 2014 Jul 18;82(7):1519-26. Epub 2014 Feb 18.

Department of Biotechnology, Hungkuang University, Taichung, 433, Taiwan; Taiwan Advance Biopharm (TABP), Inc., Xizhi City, New Taipei City, 221, Taiwan.

Uridine diphosphate N-acetylglucosamine (UDP-GlcNAc) 2-epimerase catalyzes the interconversion of UDP-GlcNAc to UDP-N-acetylmannosamine (UDP-ManNAc), which is used in the biosynthesis of cell surface polysaccharides in bacteria. Biochemical experiments have demonstrated that mutation of this enzyme causes changes in cell morphology and the thermoresistance of the cell wall. Here, we present the crystal structures of Methanocaldococcus jannaschii UDP-GlcNAc 2-epimerase in open and closed conformations. A comparison of these crystal structures shows that upon UDP and UDP-GlcNAc binding, the enzyme undergoes conformational changes involving a rigid-body movement of the C-terminal domain. We also present the crystal structure of Bacillus subtilis UDP-GlcNAc 2-epimerase in the closed conformation in the presence of UDP and UDP-GlcNAc. Although a structural overlay of these two closed-form structures reveals that the substrate-binding site is evolutionarily conserved, some areas of the allosteric site are distinct between the archaeal and bacterial UDP-GlcNAc 2-epimerases. This is the first report on the crystal structure of archaeal UDP-GlcNAc 2-epimerase, and our results clearly demonstrate the changes between the open and closed conformations of this enzyme.
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http://dx.doi.org/10.1002/prot.24516DOI Listing
July 2014

Crystallization and preliminary X-ray diffraction analysis of the DNA-binding domain of the response regulator SaeR from Staphylococcus epidermidis.

Acta Crystallogr Sect F Struct Biol Cryst Commun 2013 Jun 25;69(Pt 6):689-91. Epub 2013 May 25.

Department of Biotechnology, Hungkuang University, Taichung 433, Taiwan.

SaeR is the response regulator of the SaeRS two-component signal transduction system, which is involved in regulating bacterial autolysis and biofilm formation. SaeR comprises an N-terminal receiver domain and a C-terminal effector domain. The effector domain possesses DNA-binding and transactivation functions. Here, the effector domain of SaeR from Staphylococcus epidermidis was purified and crystallized using the sitting-drop vapour-diffusion method. The crystals diffracted to a resolution of 2.15 Å and belonged to space group P2(1)2(1)2(1), with unit-cell parameters a = 34.20, b = 53.78, c = 111.66 Å. Determining the structure will provide insights into the mechanisms underlying DNA binding.
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http://dx.doi.org/10.1107/S1744309113012943DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3668596PMC
June 2013

Crystallization and preliminary X-ray diffraction analysis of the Nif3-family protein MJ0927 from Methanocaldococcus jannaschii.

Acta Crystallogr Sect F Struct Biol Cryst Commun 2013 Jan 25;69(Pt 1):80-2. Epub 2012 Dec 25.

Department of Biotechnology, Hungkuang University, Taichung 433, Taiwan.

MJ0927 is a member of the Nif3 family and is widely distributed across living organisms. Although several crystal structures of Nif3 proteins have been reported, structural information on archaeal Nif3 is still limited. To understand the structural differences between bacterial and archaeal Nif3 proteins, MJ0927 from Methanocaldococcus jannaschii was purified and crystallized using the sitting-drop vapour-diffusion method. The crystals diffracted to a resolution of 2.47 Å and belonged to the orthorhombic space group C222, with unit-cell parameters a = 81.21, b = 172.94, c = 147.42 Å. Determination of this structure may provide insights into the function of MJ0927.
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http://dx.doi.org/10.1107/S1744309112049408DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3539711PMC
January 2013

Expression, purification, crystallization and preliminary X-ray analysis of the RecQ helicase catalytic core from Deinococcus radiodurans.

Acta Crystallogr Sect F Struct Biol Cryst Commun 2012 Oct 29;68(Pt 10):1234-6. Epub 2012 Sep 29.

Institute of Biochemistry and Molecular Biology, College of Medicine, National Taiwan University, Taipei City, 100, Taiwan.

The RecQ proteins are a highly conserved group of DNA helicases which play crucial roles in the maintenance of genome stability. DrRecQ from the radioresistant bacterium Deinococcus radiodurans is a special member of the RecQ family because it contains three Helicase-and-RNase-D-C-terminal (HRDC) domains at the C-terminus. The helicase catalytic core is essential for ATPase and DNA-unwinding activities. In this work, the helicase catalytic core of DrRecQ was expressed in Escherichia coli, purified and crystallized. Crystals were obtained using the sitting-drop vapour diffusion method and X-ray diffraction data were collected to 2.9 Å resolution. The crystals belong to space group P2(1)2(1)2(1), with unit-cell parameters a = 84.75, b = 95.61, c = 183.83 Å.
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http://dx.doi.org/10.1107/S1744309112037517DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3490466PMC
October 2012

Expression, purification, crystallization and preliminary X-ray analysis of ribitol-5-phosphate cytidylyltransferase from Bacillus subtilis.

Acta Crystallogr Sect F Struct Biol Cryst Commun 2012 Oct 26;68(Pt 10):1195-7. Epub 2012 Sep 26.

Institute of Biochemistry and Molecular Biology, College of Medicine, National Taiwan University, Taipei City 100, Taiwan.

TarI is a ribitol-5-phosphate cytidylyltransferase that catalyzes the formation of CDP-ribitol, which is involved in the biosynthesis of wall teichoic acids, from CTP and ribitol 5-phosphate. TarI from Bacillus subtilis (BsTarI) was purified and crystallized using the sitting-drop vapour-diffusion method. The crystals diffracted to a resolution of 1.78 Å and belonged to the monoclinic space group C2, with unit-cell parameters a = 103.74, b = 60.97, c = 91.80 Å, β = 113.48°. The initial structural model indicated that the crystals of BsTarI contained a dimer in the asymmetric unit.
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http://dx.doi.org/10.1107/S1744309112035142DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3497978PMC
October 2012

Expression, purification, crystallization and preliminary X-ray analysis of the D-alanyl carrier protein DltC from Staphylococcus epidermidis.

Acta Crystallogr Sect F Struct Biol Cryst Commun 2012 Jul 28;68(Pt 7):810-2. Epub 2012 Jun 28.

Department of Biotechnology, Hungkuang University, Taichung 433, Taiwan.

The D-alanyl lipoteichoic acids (D-alanyl LTAs) present in the cell walls of Gram-positive bacteria play crucial roles in autolysis, cation homeostasis and biofilm formation. The alanylation of LTAs requires the D-alanyl carrier protein DltC to transfer D-Ala onto a membrane-associated LTA. Here, DltC from Staphylococcus epidermidis (SeDltC) was purified and crystallized using the sitting-drop vapour-diffusion method. The crystals diffracted to a resolution of 1.83 Å and belonged to space group P2, with unit-cell parameters a = 66.26, b = 53.28, c = 88.05 Å, β = 98.22°. The results give a preliminary crystallographic analysis of SeDltC and shed light on the functional role of DltC in the alanylation of LTAs.
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http://dx.doi.org/10.1107/S1744309112021720DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3388928PMC
July 2012