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158 results on '"Sakamoto, Junshi"'

11. Cardiolipin enhances the enzymatic activity of cytochrome bd and cytochrome bo 3 solubilized in dodecyl-maltoside

Author

Asseri, Amer H. (author), Godoy Hernandez, A. (author), Goojani, Hojjat Ghasemi (author), Lill, Holger (author), Sakamoto, Junshi (author), McMillan, D.G.G. (author), Bald, Dirk (author), Asseri, Amer H. (author), Godoy Hernandez, A. (author), Goojani, Hojjat Ghasemi (author), Lill, Holger (author), Sakamoto, Junshi (author), McMillan, D.G.G. (author), and Bald, Dirk (author)

Abstract

Cardiolipin (CL) is a lipid that is found in the membranes of bacteria and the inner membranes of mitochondria. CL can increase the activity of integral membrane proteins, in particular components of respiratory pathways. We here report that CL activated detergent-solubilized cytochrome bd, a terminal oxidase from Escherichia coli. CL enhanced the oxygen consumption activity ~ twofold and decreased the apparent KM value for ubiquinol-1 as substrate from 95 µM to 35 µM. Activation by CL was also observed for cytochrome bd from two Gram-positive species, Geobacillus thermodenitrificans and Corynebacterium glutamicum, and for cytochrome bo3 from E. coli. Taken together, CL can enhance the activity of detergent-solubilized cytochrome bd and cytochrome bo3., BT/Biocatalysis

Published
2021
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14. The carboxy-terminal insert in the Q-loop is needed for functionality of Escherichia coli cytochrome bd-I

Author

Ghasemi Goojani, Hojjat Allah, Konings, Julia, Hakvoort, Henk, Hong, Sangjin, Gennis, Robert B., Sakamoto, Junshi, Lill, Holger, Bald, Dirk, Ghasemi Goojani, Hojjat Allah, Konings, Julia, Hakvoort, Henk, Hong, Sangjin, Gennis, Robert B., Sakamoto, Junshi, Lill, Holger, and Bald, Dirk

Abstract

Cytochrome bd, a component of the prokaryotic respiratory chain, is important under physiological stress and during pathogenicity. Electrons from quinol substrates are passed on via heme groups in the CydA subunit and used to reduce molecular oxygen. Close to the quinol binding site, CydA displays a periplasmic hydrophilic loop called Q-loop that is essential for quinol oxidation. In the carboxy-terminal part of this loop, CydA from Escherichia coli and other proteobacteria harbors an insert of ~60 residues with unknown function. In the current work, we demonstrate that growth of the multiple-deletion strain E. coli MB43∆cydA (∆cydA∆cydB∆appB∆cyoB∆nuoB) can be enhanced by transformation with E. coli cytochrome bd-I and we utilize this system for assessment of Q-loop mutants. Deletion of the cytochrome bd-I Q-loop insert abolished MB43∆cydA growth recovery. Swapping the cytochrome bd-I Q-loop for the Q-loop from Geobacillus thermodenitrificans or Mycobacterium tuberculosis CydA, which lack the insert, did not enhance the growth of MB43∆cydA, whereas swapping for the Q-loop from E. coli cytochrome bd-II recovered growth. Alanine scanning experiments identified the cytochrome bd-I Q-loop insert regions Ile318-Met322, Gln338-Asp342, Tyr353-Leu357, and Thr368-Ile372 as important for enzyme functionality. Those mutants that completely failed to recover growth of MB43∆cydA also lacked oxygen consumption activity and heme absorption peaks. Moreover, we were not able to isolate cytochrome bd-I from these inactive mutants. The results indicate that the cytochrome bd Q-loop exhibits low plasticity and that the Q-loop insert in E. coli is needed for complete, stable, assembly of cytochrome bd-I.

Published
2020
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17. Cytochrome c oxidase contains an extra charged amino acid cluster in a new type of respiratory chain in the amino-acid-producing Gram-positive bacterium Corynebacterium glutamicum

Author

Sakamoto, Junshi, Shibata, Takatsugu, Mine, Tadashi, Miyahara, Ryoko, Torigoe, Tomokimi, Noguchi, Shunsuke, Matsushita, Kazunobu, and Sone, Nobuhito

Subjects
Microbiological research -- Analysis, Gram-positive bacteria -- Physiological aspects, Amino acids -- Physiological aspects, Oxidases -- Physiological aspects, Cytochrome c -- Analysis, Biological sciences
Abstract

Research has been conducted on the membranes from Corynebacterium glutamicum cells containing cytochrome c subunit. The isolation of the cytochrome aa (sub)3 -type cytochrome c oxidase and cloning of its structural genes have been carried out and examined.

Published
2001

21. Purification and biochemical properties of a cytochrome bc complex from the aerobic hyperthermophilic archaeon Aeropyrum pernix

Author

Kabashima Yoshiki and Sakamoto Junshi

Subjects
Microbiology, QR1-502
Abstract

Abstract Background The bioenergetics of Archaea with respect to the evolution of electron transfer systems is very interesting. In contrast to terminal oxidases, a canonical bc1 complex has not yet been isolated from Archaea. In particular, c-type cytochromes have been reported only for a limited number of species. Results Here, we isolated a c-type cytochrome-containing enzyme complex from the membranes of the hyperthermophilic archaeon, Aeropyrum pernix, grown aerobically. The redox spectrum of the isolated c-type cytochrome showed a characteristic α-band peak at 553 nm corresponding to heme C. The pyridine hemochrome spectrum also revealed the presence of heme B. In non-denaturing polyacrylamide gel electrophoresis, the cytochrome migrated as a single band with an apparent molecular mass of 80 kDa, and successive SDS-PAGE separated the 80-kDa band into 3 polypeptides with apparent molecular masses of 40, 30, and 25 kDa. The results of mass spectrometry indicated that the 25-kDa band corresponded to the hypothetical cytochrome c subunit encoded by the ORF APE_1719.1. In addition, the c-type cytochrome-containing polypeptide complex exhibited menaquinone: yeast cytochrome c oxidoreductase activities. Conclusion In conclusion, we showed that A. pernix, a hyperthemophilic archaeon, has a "full" bc complex that includes a c-type cytochrome, and to the best of our knowledge, A. pernix is the first archaea from which such a bc complex has been identified. However, an electron donor candidates for cytochrome c oxidase, such as a blue copper protein, have not yet been identified in the whole genome data of this archaeon. We are currently trying to identify an authentic substrate between a bc complex and terminal oxidase.

Published
2011
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28. Supercritical CO2 extraction of essential oil from Kabosu (Citrus sphaerocarpa Tanaka) peel

Author

Suetsugu, Takuya, primary, Tanaka, Masahiro, additional, Iwai, Hideo, additional, Matsubara, Teruaki, additional, Kawamoto, Yukihiro, additional, Saito, Chiho, additional, Sasaki, Yoshito, additional, Hoshino, Munehiro, additional, Quitain, Armando T, additional, Sasaki, Mitsuru, additional, Sakamoto, Junshi, additional, and Goto, Motonobu, additional

Published
2013
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41. Aerobic Respiration in the Gram-Positive Bacteria.

Author

Govindjee, Zannoni, Davide, Sone, Nobhuito, Hagerhall, Cecilia, and Sakamoto, Junshi

Abstract

The group of Gram-positive bacteria is a major phylum of prokaryotes, including several typical saprophytic aerobes. Their respiratory chains are apparently similar to those of eukaryotic mitochondria, but in several points are different from them. The respiratory chain of Gram-positives, like many bacteria, contains branched electron transfer pathways, usually 1-3 heme-Cu oxidases, but SoxB-type cytochrome c oxidases (cytochrome b(a/o)3) are working under air-limited conditions in thermophilic and alkaliphilic Bacillus species. On the other hand, SoxM-type quinol oxidase (cytochrome aa3) is mainly working in mesophilic Bacillus subtilis. Quinol-cytochorme c reductase of low G+C content Gram-positives (Firmicutes) is composed of a Rieske Fe-S subunit, a split cytochrome b (b6-type) and a novel cytochrome c1 subunit formed from ‘subunit IV' and a kind of class-I cytochromes c, while that of high G+C content Gram-positives (Actinobacteria) has a cytochrome b, a Fe-S protein with three transmembrane helices and a novel diheme cytochrome cc, without and small cytochromes c in the cell. Some of these characteristics are due to the lack of outer membranes of Gram-positives, in which any c-type cytochrome should be anchored to the cell membrane, and other are probably due to the evolutionary history of bacteria. [ABSTRACT FROM AUTHOR]

Published
2004
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42. A novel hydrophobic diheme c -type cytochrome. Purification from Corynebacterium glutamicum and analysis of the QcrCBA operon encoding three subunit proteins of a putative cytochrome reductase complex 1The nucleotide sequences reported in this paper have been submitted to the DDBJ/GenBank/EMBL Data Bank with accession number AB038380. 1

Author

Sone, Nobuhito, primary, Nagata, Kumiko, additional, Kojima, Haruka, additional, Tajima, Junnichi, additional, Kodera, Yoriko, additional, Kanamaru, Tomoe, additional, Noguchi, Shunnsuke, additional, and Sakamoto, Junshi, additional

Published
2001
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49. Monitoring the enzyme expression in a respiratory chain of Corynebacterium glutamicumin a copper ion-supplemented culture medium

Author

Kusumoto, Tomoichirou, Aoyagi, Makoto, Sugiyama, Takahiko, and Sakamoto, Junshi

Abstract

Corynebacterium glutamicumhas a branched respiratory chain: one of the branches is cytochrome bcccomplex and cytochrome aa3-type cytochrome coxidase, and the other is cytochrome bd-type menaquinol oxidase. The factors that influence the expression patterns of these respiratory enzymes remain unclear. To investigate the expressional control mechanism of the enzymes, we have previously constructed a promoter assay system utilizing enhanced green fluorescence protein. Here, we monitored respiratory enzymes’ expression by using this system during growth in various culture media, with and without Cu2+ion supplementation. The promoter activities of cytochrome aa3oxidase in the early stationary phase in the media supplemented with Cu2+ion at 40 or 400 μM were significantly increased 1.49-fold or 1.99-fold, respectively, as compared to the control. Moreover, the H+/O ratio, or the proton-pumping activity of the cells, increased about 1.6 times by the Cu2+supplementation. These facts indicate that copper ions can switch the branches.

Published
2015
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