Design and Performance of the Okazaki Large Spectrograph for Photobiological Research

Watanabe, Masakatsu; Furuya, Masaki; Miyoshi, Y.; Inoue, Yasunori; Iwahashi, Isao; Matsumoto, Koichí

doi:10.1111/j.1751-1097.1982.tb04407.x

Cited by 183 publications

(65 citation statements)

References 19 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The design and the features of this spectrograph have already been reported. 1 The beam was focused on the surface of the samples by using a surface mirror (20 ϫ 10 cm). A schematic representation of the monochromatic radiation exposure was also given in our previous article.…”

Section: Polychromatic and Monochromatic Exposure Studiesmentioning

confidence: 99%

Effect of ultraviolet radiation on photodegradation of collagen

Torikai

Shibata

1999

J. Appl. Polym. Sci.

View full text Add to dashboard Cite

Photodegradation of solvent-cast collagen type I films and photostabilization of collagen by vitamin E were studied. These films were exposed to polychromatic radiation from a medium-pressure mercury lamp or monochromatic radiation from the Okazaki Large Spectrograph (OLS). Changes in the molecular structure of collagen were followed by UV-visible and FTIR spectroscopic measurements. Electron spin resonance (ESR) spectroscopic measurements were also carried out to identify the reaction intermediates of photodegradation. Photoreaction from phenylalanine, which is one of the main constituents of collagen to tyrosine and the scission of peptide linkage of collagen, were confirmed. Vitamin E was found to be an efficient photostabilizer for photodegradation of collagen. Action spectra of photodegradation and photostabilization of a collagen molecule were reported. A possible mechanism for the photodegradation of the collagen and photostabilization scheme based on these experimental results are presented.

show abstract

Section: Polychromatic and Monochromatic Exposure Studiesmentioning

confidence: 99%

Effect of ultraviolet radiation on photodegradation of collagen

Torikai

Shibata

1999

J. Appl. Polym. Sci.

View full text Add to dashboard Cite

show abstract

“…A spectrum covering UV, visible, and near infrared region (250-1000 nm) is projected onto a 10-mlong focal curve. The detailed description of the spectrograph was reported by Watanabe et al 7 Irradiation of monochromatic light with any desired wavelength was made by placing the samples at appropriate positions on a 10-m-long focal curve. The wavelength dispersion is about 0.8 nm/cm.…”

Section: Irradiationmentioning

confidence: 99%

Photodegradation of poly(methyl methacrylate) by monochromatic light: Quantum yield, effect of wavelengths, and light intensity

Torikai

Ohno

Fueki

1990

J of Applied Polymer Sci

118

View full text Add to dashboard Cite

SynopsisPoly( methyl methacrylate) (PMMA) was photolyzed with monochromatic light of wavelengths 260, 280, and 300 nm by the use of the Okazaki large spectrograph. The quantum yield of mainchain scission ( aC8), effects of wavelength, and incident photon intensity on the photodegradation were investigated. It turned out that photodegradation of PMMA took place by the irradiation of 260-300 nm light, but did not by the irradiation at X 2 320 nm. The number of main-chain scission ( N c s ) has a maximum value in the case of the irradiation with 280 nm light. Under the same conditions of wavelength and total photon intensity, a longer-term irradiation with a weaker incident photon intensity tends to yield a greater amount of main-chain scission. A linear relationship was found between the number of main-chain scission and the incident photon intensity. The average values of aC8 obtained in this work were 2.1 X 2.4 X and 4.1 X respectively, for the irradiations a t 260, 280, and 300 nm. It was found that the photoinduced side-chain scission initiates the main-chain scission of PMMA.

show abstract

“…Low-fluence (LF) and very-low-fluence (VLF) germination assays were carried out essentially according to Shinomura et al (37). Monochromatic irradiation was done at the Okazaki large spectrograph (38). Germination frequencies (%) are based on the presence of an emerged radicle.…”

Section: Methodsmentioning

confidence: 99%

Complementation of phytochrome chromophore-deficient Arabidopsis by expression of phycocyanobilin:ferredoxin oxidoreductase

Kami

Mukougawa

Muramoto

et al. 2004

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

The covalently bound phytochromobilin (P⌽B) prosthetic group is required for the diverse photoregulatory activities of all members of the phytochrome family in vascular plants, whereas by contrast, green algal and cyanobacterial phytochromes use the more reduced linear tetrapyrrole pigment phycocyanobilin (PCB). To assess the functional consequence of the substitution of P⌽B with PCB in plants, the phytochrome chromophore-deficient hy2 mutant of Arabidopsis was transformed with a constitutively expressed pcyA gene that encodes the cyanobacterial enzyme, PCB:ferredoxin oxidoreductase. Spectroscopic analyses of extracts from etiolated seedlings revealed that PcyA expression restored photoactive phytochrome to WT levels, albeit with blue-shifted absorption maxima, while also restoring light lability to phytochrome A. Photobiological measurements indicated that PcyA expression rescued phytochrome-mediated red high-irradiance responses, lowfluence red͞far-red (FR) photoreversible responses, and very-lowfluence responses, thus confirming that PCB can functionally substitute for P⌽B for these photoregulatory activities. Although PcyA expression failed to rescue phytochrome A-mediated FR high-irradiance responsivity to that of WT, our studies indicate that the FR high-irradiance response is fully functional in pcyA-expressing plants but shifted to shorter wavelengths, indicating that PCB can functionally complement this phytochrome-mediated response in vascular plants.

show abstract

Design and Performance of the Okazaki Large Spectrograph for Photobiological Research

Cited by 183 publications

References 19 publications

Effect of ultraviolet radiation on photodegradation of collagen

Effect of ultraviolet radiation on photodegradation of collagen

Photodegradation of poly(methyl methacrylate) by monochromatic light: Quantum yield, effect of wavelengths, and light intensity

Complementation of phytochrome chromophore-deficient Arabidopsis by expression of phycocyanobilin:ferredoxin oxidoreductase

Contact Info

Product

Resources

About