• BMB Reports
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• 제28권4호
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• pp.311-315
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• 1995

Exogenous $Cu^{2+}$ or $Zn^{2+}$ at micromolar concentration had a strong inhibitory effect on detergent-solubilized cytochrome c oxidase. A similar effect was observed when $Cu^{2+}$ was added to vesicular cytochrome c oxidase, although the extent of inhibition was significantly larger for the uncoupled state than for the coupled state. Interestingly, the inhibition by $Zn^{2+}$ was almost negligible for both the coupled and uncoupled states. These results suggest that the binding sites for $Cu^{2+}$ ions are exposed to the extravesicular side. whereas those for $Zn^{2+}$ are exposed to the matrix side. The EPR spectra of bound $Cu^{2+}$ ions at 77 K indicate that each of the first two $Cu^{2+}$ ions is ligated by three or four histidine residues, as evidenced by distinct $^{14}N$ superhyperfine splitting. These $Cu^{2+}$ ions can not be removed readily by EDTA and inhibit the enzyme activity by as much as 80%.

• Journal of Microbiology
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• 제44권3호
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• pp.284-292
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• 2006

The cbb3 cytochrome c oxidase has the dual function as a terminal oxidase and oxygen sensor in the photosynthetic bacterium, Rhodobacter sphaeroides. The cbb3 oxidase forms a signal transduction pathway together with the PrrBA two-component system that controls photosynthesis gene expression in response to changes in oxygen tension in the environment. Under aerobic conditions the cbb3 oxidase generates an inhibitory signal, which shifts the equilibrium of PrrB kinase/phosphatase activities towards the phosphatase mode. Photosynthesis genes are thereby turned off under aerobic conditions. The catalytic subunit (CcoN) of the R. sphaeroides cbb3 oxidase contains five histidine residues (H2l4, B233, H303, H320, and H444) that are conserved in all CcoN subunits of the cbb3 oxidase, but not in the catalytic subunits of other members of copper-heme superfamily oxidases. H214A mutation of CcoN affected neither catalytic activity nor sensory (signaling) function of the cbb3 oxidase, whereas H320A mutation led to almost complete loss of both catalytic activity and sensory function of the cbb3 oxidase. H233V and H444A mutations brought about the partial loss of catalytic activity and sensory function of the cbb3 oxidase. Interestingly, the H303A mutant form of the cbb3 oxidase retains the catalytic function as a cytochrome c oxidase as compared to the wild-type oxidase, while it is defective in signaling function as an oxygen sensor. H303 appears to be implicated in either signal sensing or generation of the inhibitory signal to the PrrBA two-component system.

• 생명과학회지
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• 제19권7호
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• pp.852-858
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• 2009

호흡전자전달계의 cytochrome bc$_1$ complex 또는 cytochrome c oxidase가 기능을 하지 않는 Rhodobacter sphaeroides mutant 내에서 pyridine nucleotide[NAD(P)H와 NAD(P)$^+$]의 농도와 redox 상태는 wild type과 비교할 때 큰 변화가 없었다. 높은 산소분압 조건에서 키운 Rhodobacter sphaeroides cbb$_3$ oxidase mutant 내에서 PrrBA two-component system에 의해서 조절되는 puf 오페론의 발현은 pyridine nucleotide나 전자전달계의 ubiquinone/ubiquinol pool의 redox 상태의 변화에 의해 유도된 것이 아니다. R. sphaeroides cytochrome bc$_1$ complex mutant를 이용하여 광합성기구 합성에 대한 cbb$_3$ cytochrome c oxidase의 억제 효과는 ubiquinone/ubiquinol pool의 redox 변화에 의해 간접적으로 일어나는 것이 아님을 증명하였다.

• 통합자연과학논문집
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• 제15권2호
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• pp.63-72
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• 2022

To elucidate the neurochemical characteristics of the midbrain periaqueductal gray (PAG), the distribution patterns of several neuroanatomical markers within the PAG were compared. Immunohistochemical staining for the intracellular calcium binding proteins including calbindin, calretinin, and parvalbumin and histochemical staining for cytochrome oxidase, acetylcholinesterase, and NADPH-diaphorase were performed in. Each chemical substance were localized in the specific subregions within PAG. Calbindin- immunoreactivity were selectively distributed in the dorsolateral PAG, the ventral half of lateral PAG, the ventralateral PAG, and supraoculomotor cap (Su3C) nucleus. Distribution of calretinin-immunoreactivity were generally similar with that of clabindin, but showed relatively low subregional selectivity. Parvalbumin-immunoreactivity was very poor within the PAG. High reactivity of cytochrome oxidase were found in the dorsomedial PAG and the lateral half of lateral PAG, in which calbindin- and calretinin-immunoreactive perikarya were scarcely observed. Acetylcholinesterase distribution was similar with that of cytochrome oxidase, and the difference was in the additional marking of of Su3C with acetylcholinesterase. Results of the present study provides data for the further subdivisions of the territory of the PAG compared to the presently accepted subregions within the PAG.

• 미생물학회지
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• 제29권2호
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• pp.92-96
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• 1991

The soluble cytochrome c-551 of photosynthetic bacterium, Rhodopseudomonas gelatinosa ATCC 17013 was purified through a sequene of four step chromatography including CM-cellulose ion-exchange chromatography, DEAE-Sephacel chromatography, Sephacryl s-200 gel permeation chromatography, and HPLC (SP-5PW). The molecular weight of the purified cytochrome c-551 was 14, 600 Da, and this protein shows the absorption peak at 551 nm, 522 nm, and 417 nm as the reduced form, and at 412 nm as the oxidized form. The cytochrome c-551 seems to be a substrate for the terminal oxidase in the electron transport chain.

• 대한수의학회지
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• 제29권4호
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• pp.425-431
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• 1989

This study was undertaken to investigate the changes of enzyme activities resulted from low concentrated carbon monoxide poisoning on the caudate nucleus in rat. The activities of cytochrome oxidase, succinate dehydrogenase and lactate dehydragenase were observed histochemically, after the experimental animals were poisoned to 100ppm carbon monoxide for 8 hours every day from one day to 16 days. The materials were sliced from coronal section at the level of the optic chiasm and immediately frozen sections of $10{\mu}m$ thickness were cut on the cryostat at $-15^{\circ}C$ and incubated in the medium containing substrate for histochemical detection of cytochrome oxidase, succinate dehydrogenase and lactate dehydrogenase. The sections were mounted in glycerol gelatin and observed under light microscope. It was obtained that cytochrome oxidase activity decreased moderately and succinate dehydrogenase activity showed marked or moderate activity during entire poisoning period and lactate dehydrogenase activity showed marked or moderate activity from one to 8 days but recovered to normal condition at 16th day.

• Journal of the Korean Wood Science and Technology
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• 제38권2호
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• pp.135-139
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• 2010

Reticulitermes speratus is commonly found in Asia, including Korea and Japan. We recently analyzed the 5' region of mitochondrial cytochrome c oxidase subunit I to perform a phylogenetic analysis of R. speratus KMT1, isolated in Seoul, Korea. Our results, using COXI, suggest that the taxonomy of R. speratus should be reconsidered with regard to the subgenus group. A similar phylogenetic analysis by COXI and COXII demonstrated the reliability of COXI genetic information in a molecular phylogenetic analysis of termites.

• 한국수산과학회지
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• 제29권6호
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• pp.876-881
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• 1996

To determine the amount of genetic variation among populations of Penaeus chinensis (Osbeck) in the Yellow Sea, 342 bp region of the mitochondrial cytochrome c oxidase subunit I gene was amplified and sequenced. Six haplotypes, which differ by from one to four nucleotide sustitutions, were detected from 34 individuals of 4 populations examined. Mean sequence divergence between pairs of haplotypes was $0.68\%$. Most individuals from 4 populations were shared by the most common genotype. This genotype was distributed evenly in the Korean and Chinese populations. This result is in accordance with findings observed using RFLPs analysis of mtDNA (Hwang et al., 1997). Therefore, it is suggested that P. chinensis should be treated as one unit stock in the Yellow Sea.

• Korean Journal of Acupuncture
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• 제36권4호
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• pp.200-209
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• 2019

Objectives : The liver is rich in mitochondria and it plays a key role in whole-body energy homeostasis. Mitochondria is double membrane-bound organelle that supplies energy for intracellular metabolism including Krebs cycle and beta-oxidation. Acupuncture is known to stimulate and regulate the flow of energy. To explore the effect of acupuncture on the mitochondrial respiratory chain activity in the rats' livers, the activity of mitochondrial respiratory chain complexes I to IV was observed. Methods : The rats were divided into 4 groups; Normal 1 (no acupuncture treatment and anesthesia for 5 min), Normal 2 (no acupuncture treatment and anesthesia for 10 min), MA1 (acupuncture treatment at bilateral LR3 under anesthesia for 5 min), and MA2 (acupuncture treatment at bilateral LR3 under anesthesia for 10 min). All rats were sacrificed and the livers were examined for respiratory chain change. Results : There was no difference in ubiquinon oxidoreductase, succinate dehydrogenase, and ubiquinol cytochrome C oxidoreductase after acupuncture at LR3. Acupuncture at LR3 for 10 min increased the activity of cytochrome C oxidase compared with no acupuncture groups. Conclusions : Acupuncture at LR3 mediated mitochondrial respiratory chain activity via the cytochrome C oxidase signaling pathway in the livers of rats.

• 대한약리학회지
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• 제23권2호
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• pp.113-121
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• 1987

국소마취제가 mitochondria에서의 전자이동 및 superoxide라디칼의 생성 그리고 지질의 과산화에 따른 malondialdehyde생성에 미치는 영향을 관찰하였다. 국소마취제는 전자이동계 의 효소활성도에 영향을 나타내었다. NADH dehydrogenase, NADH oxidase와 NADH-ubiquinone oxidoreductase의 활성도는 lidocaine, procaine과 dibucaine에 의하여 효과적으로 억제되었고 cocaine에 의하여 약간 억제되었다. Succinate dehydrogenase, succinate cytochrome c oxidoreductase와 succinate-ubiquinone oxidoreductase 활성도는 lidocaine 과 dibucaine에 의하여 억제되었으나 succinate oxidase는 국소마취제에 의하여 활성화되었다. 국소마취제는 dihydroubiquinone-cytochrome c oxidoreducatse와 cytochrome c oxidase의 활성도를 억제하였다. 이와 같은 반응에서 국소마취제에 대한 complex I segment의 반응이 다른 complex segment보다 크게 나타났다. 국소마취제는 succinate 또는 NADH에 의한 superoxide 생성과 이에 대한 antimycin의 자극효과를 억제하였다. 또한 국소마취제는 산소라디칼에 의한 지질의 과산화를 억제하였다. 이상의 결과로부터 국소마취제는 mitochondria의 전자전달 과정 중 Complex I segment때 또는 인접한 부위에 작용하여 전자이동을 억제함으로써 superoxide 생성과 지질의 과산화를 억제할 것으로 시사되었다.