Search

Your search keyword '"Guan, Hong-Hsiang"' showing total 125 results
Start Over Author "Guan, Hong-Hsiang"
125 results on '"Guan, Hong-Hsiang"'

2. Structure-Based High-Efficiency Homogeneous Antibody Platform by Endoglycosidase Sz Provides Insights into Its Transglycosylation Mechanism

Author

Hsieh, Yin-Cheng, primary, Guan, Hong-Hsiang, additional, Lin, Chien-Chih, additional, Huang, Teng-Yi, additional, Chuankhayan, Phimonphan, additional, Chen, Nai-Chi, additional, Wang, Nan-Hsuan, additional, Hu, Pu-Ling, additional, Tsai, Yi-Chien, additional, Huang, Yen-Chieh, additional, Yoshimura, Masato, additional, Lin, Pei-Ju, additional, Hsieh, Yih-Huang, additional, and Chen, Chun-Jung, additional

Published
2024
Full Text
View/download PDF

11. Structural insights into the histidine-containing phosphotransfer protein and receiver domain of sensor histidine kinase suggest a complex model in the two-component regulatory system inPseudomonas aeruginosa

Author

Chen, Shao-Kang, primary, Guan, Hong-Hsiang, additional, Wu, Pei-Hsun, additional, Lin, Li-Ting, additional, Wu, Meng-Chun, additional, Chang, Hwan-You, additional, Chen, Nai-Chi, additional, Lin, Chien-Chih, additional, Chuankhayan, Phimonphan, additional, Huang, Yen-Chieh, additional, Lin, Pei-Ju, additional, and Chen, Chun-Jung, additional

Published
2020
Full Text
View/download PDF

14. Characterization of Dimeric Interactions within Protrusion-Domain Interfaces of Parallel and X-Shaped Conformations of Macrobrachium rosenbergii Nodavirus: A Theoretical Study Using the DFT Method along with QTAIM and NBO Analyses

Author

Astani, Elahe K., primary, Chen, Nai-Chi, additional, Huang, Yen-Chieh, additional, Ersali, Sara, additional, Lin, Pei-Ju, additional, Guan, Hong-Hsiang, additional, Lin, Chien-Chih, additional, Chuankhayan, Phimonphan, additional, and Chen, Chun-Jung, additional

Published
2020
Full Text
View/download PDF

16. Structure–function study of AKR4C14, an aldo‐keto reductase from Thai jasmine rice (Oryza sativa L. ssp. indica cv. KDML105).

Author

Songsiriritthigul, Chomphunuch, Narawongsanont, Rawint, Tantitadapitak, Chonticha, Guan, Hong-Hsiang, and Chen, Chun-Jung

Subjects
ALDO-keto reductases, ALCOHOL dehydrogenase, JASMINE, RICE, CRYSTAL structure, ALDEHYDES, MALONDIALDEHYDE, METALLOTHIONEIN
Abstract

Aldo‐keto reductases (AKRs) are NADPH/NADP+‐dependent oxidoreductase enzymes that metabolize an aldehyde/ketone to the corresponding alcohol. AKR4C14 from rice exhibits a much higher efficiency in metabolizing malondialdehyde (MDA) than do the Arabidopsis enzymes AKR4C8 and AKR4C9, despite sharing greater than 60% amino‐acid sequence identity. This study confirms the role of rice AKR4C14 in the detoxification of methylglyoxal and MDA, and demonstrates that the endogenous contents of both aldehydes in transgenic Arabidopsis ectopically expressing AKR4C14 are significantly lower than their levels in the wild type. The apo structure of indica rice AKR4C14 was also determined in the absence of the cofactor, revealing the stabilized open conformation. This is the first crystal structure in AKR subfamily 4C from rice to be observed in the apo form (without bound NADP+). The refined AKR4C14 structure reveals a stabilized open conformation of loop B, suggesting the initial phase prior to cofactor binding. Based on the X‐ray crystal structure, the substrate‐ and cofactor‐binding pockets of AKR4C14 are formed by loops A, B, C and β1α1. Moreover, the residues Ser211 and Asn220 on loop B are proposed as the hinge residues that are responsible for conformational alteration while the cofactor binds. The open conformation of loop B is proposed to involve Phe216 pointing out from the cofactor‐binding site and the opening of the safety belt. Structural comparison with other AKRs in subfamily 4C emphasizes the role of the substrate‐channel wall, consisting of Trp24, Trp115, Tyr206, Phe216, Leu291 and Phe295, in substrate discrimination. In particular, Leu291 could contribute greatly to substrate selectivity, explaining the preference of AKR4C14 for its straight‐chain aldehyde substrate. [ABSTRACT FROM AUTHOR]

Published
2020
Full Text
View/download PDF

17. Structural insights into the electron/proton transfer pathways in the quinol:fumarate reductase from Desulfovibrio gigas

Author

Guan, Hong-Hsiang, primary, Hsieh, Yin-Cheng, additional, Lin, Pei-Ju, additional, Huang, Yen-Chieh, additional, Yoshimura, Masato, additional, Chen, Li-Ying, additional, Chen, Shao-Kang, additional, Chuankhayan, Phimonphan, additional, Lin, Chien-Chih, additional, Chen, Nai-Chi, additional, Nakagawa, Atsushi, additional, Chan, Sunney I., additional, and Chen, Chun-Jung, additional

Published
2018
Full Text
View/download PDF

24. Crystal Structures of a Piscine Betanodavirus: Mechanisms of Capsid Assembly and Viral Infection

Author

Chen, Nai-Chi, primary, Yoshimura, Masato, additional, Guan, Hong-Hsiang, additional, Wang, Ting-Yu, additional, Misumi, Yuko, additional, Lin, Chien-Chih, additional, Chuankhayan, Phimonphan, additional, Nakagawa, Atsushi, additional, Chan, Sunney I., additional, Tsukihara, Tomitake, additional, Chen, Tzong-Yueh, additional, and Chen, Chun-Jung, additional

Published
2015
Full Text
View/download PDF

25. Structures of the hydrolase domain of zebrafish 10-formyltetrahydrofolate dehydrogenase and its complexes reveal a complete set of key residues for hydrolysis and product inhibition

Author

Lin, Chien-Chih, primary, Chuankhayan, Phimonphan, additional, Chang, Wen-Ni, additional, Kao, Tseng-Ting, additional, Guan, Hong-Hsiang, additional, Fun, Hoong-Kun, additional, Nakagawa, Atsushi, additional, Fu, Tzu-Fun, additional, and Chen, Chun-Jung, additional

Published
2015
Full Text
View/download PDF

29. Crystal Structures of Complexes of the Branched-Chain Aminotransferase from Deinococcus radiodurans with α-Ketoisocaproate and l- Glutamate Suggest the Radiation Resistance of This Enzyme for Catalysis

Author

Chen, Chung-De, primary, Lin, Chih-Hao, additional, Chuankhayan, Phimonphan, additional, Huang, Yen-Chieh, additional, Hsieh, Yin-Cheng, additional, Huang, Tien-Feng, additional, Guan, Hong-Hsiang, additional, Liu, Ming-Yih, additional, Chang, Wen-Chang, additional, and Chen, Chun-Jung, additional

Published
2012
Full Text
View/download PDF

30. Crystal Structures of Aspergillus japonicus Fructosyltransferase Complex with Donor/Acceptor Substrates Reveal Complete Subsites in the Active Site for Catalysis

Author

Chuankhayan, Phimonphan, primary, Hsieh, Chih-Yu, additional, Huang, Yen-Chieh, additional, Hsieh, Yi-You, additional, Guan, Hong-Hsiang, additional, Hsieh, Yin-Cheng, additional, Tien, Yueh-Chu, additional, Chen, Chung-De, additional, Chiang, Chien-Min, additional, and Chen, Chun-Jung, additional

Published
2010
Full Text
View/download PDF

32. Structure ofBacillus amyloliquefaciensα-amylase at high resolution: implications for thermal stability

Author

Alikhajeh, Jahan, primary, Khajeh, Khosro, additional, Ranjbar, Bijan, additional, Naderi-Manesh, Hossein, additional, Lin, Yi-Hung, additional, Liu, Enhung, additional, Guan, Hong-Hsiang, additional, Hsieh, Yin-Cheng, additional, Chuankhayan, Phimonphan, additional, Huang, Yen-Chieh, additional, Jeyaraman, Jeyakanthan, additional, Liu, Ming-Yih, additional, and Chen, Chun-Jung, additional

Published
2010
Full Text
View/download PDF

38. Purification, crystallization and preliminary X-ray crystallographic analysis of the phosphatase domain (PA3346PD) of the response regulator PA3346 from Pseudomonas aeruginosa PAO1.

Author

Chen, Li-Ying, Wu, Pei-Hsun, Guan, Hong-Hsiang, Fun, Hoong-Kun, Chang, Hwan-You, and Chen, Chun-Jung

Subjects
PHOSPHOPROTEIN phosphatases, PSEUDOMONAS aeruginosa, CRYSTALLIZATION, X-ray crystallography, DIFFUSION, ESCHERICHIA coli, CRYSTALS
Abstract

The phosphatase domain (PA3346PD) of the response regulator PA3346 modulates the downstream anti-anti-σ factor PA3347 to regulate swarming motility in Pseudomonas aeruginosa PAO1. PA3346PD, which comprises the protein phosphatase 2C domain (PP2C), is classified as a Ser/Thr phosphatase of the Mg2+- or Mn2+-dependent protein phosphatase (PPM) family. The recombinant PA3346PD, with molecular mass 26 kDa, was overexpressed in Escherichia coli, purified on an Ni2+-NTA agarose column and crystallized by the sitting-drop vapour-diffusion method. X-ray diffraction data were collected from PA3346PD crystals to a resolution of 2.58 Å and the crystals belonged to space group I4132 or I4332, with unit-cell parameter a = 157.61 Å. Preliminary analysis indicates the presence of a monomer of PA3346PD in the asymmetric unit with a solvent content of 58.4%. [ABSTRACT FROM AUTHOR]

Published
2015
Full Text
View/download PDF

43. Direct phase selection of initial phases from single-wavelength anomalous dispersion (SAD) for the improvement of electron density and ab initio structure determination.

Author

Chen, Chung-De, Huang, Yen-Chieh, Chiang, Hsin-Lin, Hsieh, Yin-Cheng, Guan, Hong-Hsiang, Chuankhayan, Phimonphan, and Chen, Chun-Jung

Subjects
ELECTRON density, DISPERSION (Chemistry), MACROMOLECULES, SUBSTITUENTS (Chemistry), X-ray crystallography
Abstract

Optimization of the initial phasing has been a decisive factor in the success of the subsequent electron-density modification, model building and structure determination of biological macromolecules using the single-wavelength anomalous dispersion (SAD) method. Two possible phase solutions (ϕ1 and ϕ2) generated from two symmetric phase triangles in the Harker construction for the SAD method cause the well known phase ambiguity. A novel direct phase-selection method utilizing the θDS list as a criterion to select optimized phases ϕam from ϕ1 or ϕ2 of a subset of reflections with a high percentage of correct phases to replace the corresponding initial SAD phases ϕSAD has been developed. Based on this work, reflections with an angle θDS in the range 35-145° are selected for an optimized improvement, where θDS is the angle between the initial phase ϕSAD and a preliminary density-modification (DM) phase ϕDMNHL. The results show that utilizing the additional direct phase-selection step prior to simple solvent flattening without phase combination using existing DM programs, such as RESOLVE or DM from CCP4, significantly improves the final phases in terms of increased correlation coefficients of electron-density maps and diminished mean phase errors. With the improved phases and density maps from the direct phase-selection method, the completeness of residues of protein molecules built with main chains and side chains is enhanced for efficient structure determination. [ABSTRACT FROM AUTHOR]

Published
2014
Full Text
View/download PDF

44. Structure of Bacillus amyloliquefaciensα-amylase at high resolution: implications for thermal stability.

Author

Alikhajeh, Jahan, Khajeh, Khosro, Ranjbar, Bijan, Naderi-Manesh, Hossein, Lin, Yi-Hung, Liu, Enhung, Guan, Hong-Hsiang, Hsieh, Yin-Cheng, Chuankhayan, Phimonphan, Huang, Yen-Chieh, Jeyaraman, Jeyakanthan, Liu, Ming-Yih, and Chen, Chun-Jung

Subjects
CRYSTAL structure research, BACILLUS amyloliquefaciens, AMYLASES, THERMAL stability, BACILLUS licheniformis
Abstract

The crystal structure of Bacillus amyloliquefaciensα-amylase (BAA) at 1.4 Å resolution revealed ambiguities in the thermal adaptation of homologous proteins in this family. The final model of BAA is composed of two molecules in a back-to-back orientation, which is likely to be a consequence of crystal packing. Despite a high degree of identity, comparison of the structure of BAA with those of other liquefying-type α-amylases indicated moderate discrepancies at the secondary-structural level. Moreover, a domain-displacement survey using anisotropic B-factor and domain-motion analyses implied a significant contribution of domain B to the total flexibility of BAA, while visual inspection of the structure superimposed with that of B. licheniformisα-amylase (BLA) indicated higher flexibility of the latter in the central domain A. Therefore, it is suggested that domain B may play an important role in liquefying α-amylases, as its rigidity offers a substantial improvement in thermostability in BLA compared with BAA. [ABSTRACT FROM AUTHOR]

Published
2010
Full Text
View/download PDF

45. Crystal structure of a secondary vitamin D3 binding site of milk β-lactoglobulin.

Author

Yang, Ming-Chi, Guan, Hong-Hsiang, Liu, Ming-Yih, Lin, Yih-Hung, Yang, Jinn-Moon, Chen, Wen-Liang, Chen, Chun-Jung, and Mao, Simon J. T.

Abstract

β-lactoglobulin (β-LG), one of the most investigated proteins, is a major bovine milk protein with a predominantly β structure. The structural function of the only α-helix with three turns at the C-terminus is unknown. Vitamin D3 binds to the central calyx formed by the β-strands. Whether there are two vitamin D binding-sites in each β-LG molecule has been a subject of controversy. Here, we report a second vitamin D3 binding site identified by synchrotron X-ray diffraction (at 2.4 Å resolution). In the central calyx binding mode, the aliphatic tail of vitamin D3 clearly inserts into the binding cavity, where the 3-OH group of vitamin D3 binds externally. The electron density map suggests that the 3-OH group interacts with the carbonyl of Lys-60 forming a hydrogen bond (2.97 Å). The second binding site, however, is near the surface at the C-terminus (residues 136-149) containing part of an α-helix and a β-strand I with 17.91 Å in length, while the span of vitamin D3 is about 12.51 Å. A remarkable feature of the second exosite is that it combines an amphipathic α-helix providing nonpolar residues (Phe-136, Ala-139, and Leu-140) and a β-strand providing a nonpolar (Ile-147) and a buried polar residue (Arg-148). They are linked by a hydrophobic loop (Ala-142, Leu-143, Pro-144, and Met-145). Thus, the binding pocket furnishes strong hydrophobic force to stabilize vitamin D3 binding. This finding provides a new insight into the interaction between vitamin D3 and β-LG, in which the exosite may provide another route for the transport of vitamin D3 in vitamin D3 fortified dairy products. Atomic coordinates for the crystal structure of β-LG-vitamin D3 complex described in this work have been deposited in the PDB (access code 2GJ5). Proteins 2008. © 2007 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Published
2008
Full Text
View/download PDF

46. Purification, crystallization and preliminary X-ray crystallographic analysis of rice bifunctional α-amylase/subtilisin inhibitor from Oryza sativa.

Author

Lin, Yi-Hung, Peng, Wen-Yan, Huang, Yen-Chieh, Guan, Hong-Hsiang, Liu, Ming-Yih, Chang, Tschining, Hsieh, Ying-Cheng, and Chen, Chun-Jung

Subjects
RICE, CRYSTALLIZATION, X-ray diffraction, SUBTILISIN inhibitors, SUBTILISINS
Abstract

Rice bifunctional α-amylase/subtilisin inhibitor (RASI) can inhibit both α-­amylase from larvae of the red flour beetle ( Tribolium castaneum) and subtilisin from Bacillus subtilis. The synthesis of RASI is up-regulated during the late milky stage in developing seeds. The 8.9 kDa molecular-weight RASI from rice has been crystallized using the hanging-drop vapour-diffusion method. According to 1.81 Å resolution X-ray diffraction data from rice RASI crystals, the crystal belongs to space group P21212, with unit-cell parameters a = 79.99, b = 62.95, c = 66.70 Å. Preliminary analysis indicates two RASI molecules in an asymmetric unit with a solvent content of 44%. [ABSTRACT FROM AUTHOR]

Published
2006
Full Text
View/download PDF

47. Structural insights into the electron/proton transfer pathways in the quinol : fumarate reductase from Desulfovibrio gigas

Author

Guan, Hong-Hsiang, Hsieh, Yin-Cheng, Lin, Pei-Ju, Huang, Yen-Chieh, Yoshimura, Masato, Chen, Li-Ying, Chen, Shao-Kang, Chuankhayan, Phimonphan, Lin, Chien-Chih, Chen, Nai-Chi, Nakagawa, Atushi, Chan, Sunny I., Chen, Chun-Jung, Guan, Hong-Hsiang, Hsieh, Yin-Cheng, Lin, Pei-Ju, Huang, Yen-Chieh, Yoshimura, Masato, Chen, Li-Ying, Chen, Shao-Kang, Chuankhayan, Phimonphan, Lin, Chien-Chih, Chen, Nai-Chi, Nakagawa, Atushi, Chan, Sunny I., and Chen, Chun-Jung

Abstract

Guan, H., Hsieh, Y., Lin, P. et al. Structural insights into the electron/proton transfer pathways in the quinol : fumarate reductase from Desulfovibrio gigas. Sci Rep 8, 14935 (2018) doi:10.1038/s41598-018-33193-5, The membrane-embedded quinol: fumarate reductase (QFR) in anaerobic bacteria catalyzes the reduction of fumarate to succinate by quinol in the anaerobic respiratory chain. The electron/protontransfer pathways in QFRs remain controversial. Here we report the crystal structure of QFR from the anaerobic sulphate-reducing bacterium Desulfovibrio gigas (D. gigas) at 3.6 Å resolution. The structure of the D. gigas QFR is a homo-dimer, each protomer comprising two hydrophilic subunits, A and B, and one transmembrane subunit C, together with six redox cofactors including two b-hemes. One menaquinone molecule is bound near heme bL in the hydrophobic subunit C. This location of the menaquinone-binding site differs from the menaquinol-binding cavity proposed previously for QFR from Wolinella succinogenes. The observed bound menaquinone might serve as an additional redox cofactor to mediate the proton-coupled electron transport across the membrane. Armed with these structuralinsights, we propose electron/proton-transfer pathways in the quinol reduction of fumarate to succinate in the D. gigas QFR.

48. Crystal Structures of a Piscine Betanodavirus : Mechanisms of Capsid Assembly and Viral Infection

Author

Chen, Nai-Chi, Yoshimura, Masato, Guan, Hong-Hsiang, Wang, Ting-Yu, Misumi, Yuko, Lin, Chien-Chih, Chuankhayan, Phimonphan, Nakagawa, Atushi, Chan, Sunney I., Tsukihara, Tomitake, Chen, Tzong-Yueh, Chen, Chun-Jung, Chen, Nai-Chi, Yoshimura, Masato, Guan, Hong-Hsiang, Wang, Ting-Yu, Misumi, Yuko, Lin, Chien-Chih, Chuankhayan, Phimonphan, Nakagawa, Atushi, Chan, Sunney I., Tsukihara, Tomitake, Chen, Tzong-Yueh, and Chen, Chun-Jung

Abstract

Chen NC, Yoshimura M, Guan HH, Wang TY, Misumi Y, et al. (2015) Crystal Structures of a Piscine Betanodavirus : Mechanisms of Capsid Assembly and Viral Infection. PLOS Pathogens 11(10): e1005203. https://doi.org/10.1371/journal.ppat.1005203, Betanodaviruses cause massive mortality in marine fish species with viral nervous necrosis. The structure of a T = 3 Grouper nervous necrosis virus-like particle (GNNV-LP) is determined by the ab initio method with non-crystallographic symmetry averaging at 3.6 Å resolution. Each capsid protein (CP) shows three major domains: (i) the N-terminal arm, an intersubunit extension at the inner surface; (ii) the shell domain (S-domain), a jelly-roll structure; and (iii) the protrusion domain (P-domain) formed by three-fold trimeric protrusions. In addition, we have determined structures of the T = 1 subviral particles (SVPs) of (i) the delta-Pdomain mutant (residues 35−217) at 3.1 Å resolution; and (ii) the N-ARM deletion mutant (residues 35−338) at 7 Å resolution; and (iii) the structure of the individual P-domain (residues 214−338) at 1.2 Å resolution. The P-domain reveals a novel DxD motif asymmetrically coordinating two Ca^<2+> ions, and seems to play a prominent role in the calcium-mediated trimerization of the GNNV CPs during the initial capsid assembly process. The flexible N-ARM (N-terminal arginine-rich motif) appears to serve as a molecular switch for T = 1 or T = 3 assembly. Finally, we find that polyethylene glycol, which is incorporated into the Pdomain during the crystallization process, enhances GNNV infection. The present structural studies together with the biological assays enhance our understanding of the role of the Pdomain of GNNV in the capsid assembly and viral infection by this betanodavirus.

49. Crystal Structures of a Piscine Betanodavirus : Mechanisms of Capsid Assembly and Viral Infection

Author

Chen, Nai-Chi, Yoshimura, Masato, Guan, Hong-Hsiang, Wang, Ting-Yu, Misumi, Yuko, Lin, Chien-Chih, Chuankhayan, Phimonphan, Nakagawa, Atushi, Chan, Sunney I., Tsukihara, Tomitake, Chen, Tzong-Yueh, Chen, Chun-Jung, Chen, Nai-Chi, Yoshimura, Masato, Guan, Hong-Hsiang, Wang, Ting-Yu, Misumi, Yuko, Lin, Chien-Chih, Chuankhayan, Phimonphan, Nakagawa, Atushi, Chan, Sunney I., Tsukihara, Tomitake, Chen, Tzong-Yueh, and Chen, Chun-Jung

Abstract

Chen NC, Yoshimura M, Guan HH, Wang TY, Misumi Y, et al. (2015) Crystal Structures of a Piscine Betanodavirus : Mechanisms of Capsid Assembly and Viral Infection. PLOS Pathogens 11(10): e1005203. https://doi.org/10.1371/journal.ppat.1005203, Betanodaviruses cause massive mortality in marine fish species with viral nervous necrosis. The structure of a T = 3 Grouper nervous necrosis virus-like particle (GNNV-LP) is determined by the ab initio method with non-crystallographic symmetry averaging at 3.6 Å resolution. Each capsid protein (CP) shows three major domains: (i) the N-terminal arm, an intersubunit extension at the inner surface; (ii) the shell domain (S-domain), a jelly-roll structure; and (iii) the protrusion domain (P-domain) formed by three-fold trimeric protrusions. In addition, we have determined structures of the T = 1 subviral particles (SVPs) of (i) the delta-Pdomain mutant (residues 35−217) at 3.1 Å resolution; and (ii) the N-ARM deletion mutant (residues 35−338) at 7 Å resolution; and (iii) the structure of the individual P-domain (residues 214−338) at 1.2 Å resolution. The P-domain reveals a novel DxD motif asymmetrically coordinating two Ca^<2+> ions, and seems to play a prominent role in the calcium-mediated trimerization of the GNNV CPs during the initial capsid assembly process. The flexible N-ARM (N-terminal arginine-rich motif) appears to serve as a molecular switch for T = 1 or T = 3 assembly. Finally, we find that polyethylene glycol, which is incorporated into the Pdomain during the crystallization process, enhances GNNV infection. The present structural studies together with the biological assays enhance our understanding of the role of the Pdomain of GNNV in the capsid assembly and viral infection by this betanodavirus.

50. Structural insights into the electron/proton transfer pathways in the quinol : fumarate reductase from Desulfovibrio gigas

Author

Guan, Hong-Hsiang, Hsieh, Yin-Cheng, Lin, Pei-Ju, Huang, Yen-Chieh, Yoshimura, Masato, Chen, Li-Ying, Chen, Shao-Kang, Chuankhayan, Phimonphan, Lin, Chien-Chih, Chen, Nai-Chi, Nakagawa, Atushi, Chan, Sunny I., Chen, Chun-Jung, Guan, Hong-Hsiang, Hsieh, Yin-Cheng, Lin, Pei-Ju, Huang, Yen-Chieh, Yoshimura, Masato, Chen, Li-Ying, Chen, Shao-Kang, Chuankhayan, Phimonphan, Lin, Chien-Chih, Chen, Nai-Chi, Nakagawa, Atushi, Chan, Sunny I., and Chen, Chun-Jung

Abstract

Guan, H., Hsieh, Y., Lin, P. et al. Structural insights into the electron/proton transfer pathways in the quinol : fumarate reductase from Desulfovibrio gigas. Sci Rep 8, 14935 (2018) doi:10.1038/s41598-018-33193-5, The membrane-embedded quinol: fumarate reductase (QFR) in anaerobic bacteria catalyzes the reduction of fumarate to succinate by quinol in the anaerobic respiratory chain. The electron/protontransfer pathways in QFRs remain controversial. Here we report the crystal structure of QFR from the anaerobic sulphate-reducing bacterium Desulfovibrio gigas (D. gigas) at 3.6 Å resolution. The structure of the D. gigas QFR is a homo-dimer, each protomer comprising two hydrophilic subunits, A and B, and one transmembrane subunit C, together with six redox cofactors including two b-hemes. One menaquinone molecule is bound near heme bL in the hydrophobic subunit C. This location of the menaquinone-binding site differs from the menaquinol-binding cavity proposed previously for QFR from Wolinella succinogenes. The observed bound menaquinone might serve as an additional redox cofactor to mediate the proton-coupled electron transport across the membrane. Armed with these structuralinsights, we propose electron/proton-transfer pathways in the quinol reduction of fumarate to succinate in the D. gigas QFR.

Catalog

Books, media, physical & digital resources
See catalog results