X-ray induced inactivation of the capacity for photosynthetic oxygen evolution and nitrate reduction in blue-green algae

Journal Article · Mon Sep 01 04:00:00 EDT 1975 · Radiat. Res., v. 63, no. 3, pp. 395-402

DOI:https://doi.org/10.2307/3574092· OSTI ID:4157823

Stevens, S E; Simic, M G; Rao, V S.K.

The level of inactivation of oxygen evolving photosynthesis in the green alga, Chlorella pyrenoidosa was 12 percent in N$sub 2$ at a dose of 100 krad of x irradiation. Under similar conditions, as well as under O$sub 2$, there resulted a 20 percent inactivation of the same function in the blue-green algae, Agmenellum quadruplicatum, strains PR-6 and AQ-6. Nitrate reduction capacity in the mutant AQ-6 was inactivated to 40 percent in N$sub 2$ and to 7 percent in O$sub 2$. Catalase and formate provided some protection from irradiation in O$sub 2$, suggesting some inactivation by H$sub 2$$O$$sub 2$. Most of the damage to the nitrate reduction system resulted from the direct action of x irradiation on a constitutive subunit of the nitrate reductase complex. Moreover, the slight inactivation of the O$sub 2$ evolving system, a function which is associated with photosystem II, cannot account for the inactivation of nitrate reduction. (auth)

• Research Organization: Univ. of Texas, Austin
• Sponsoring Organization: USDOE
• NSA Number: NSA-33-007444
• OSTI ID: 4157823
• Journal Information: Radiat. Res., v. 63, no. 3, pp. 395-402, Journal Name: Radiat. Res., v. 63, no. 3, pp. 395-402; ISSN RAREA
• Country of Publication: United States
• Language: English

Related Subjects

*CATALASE-- RADIOSENSITIVITY EFFECTS
*FORMATES-- RADIOSENSITIVITY EFFECTS
*PHOTOSYNTHESIS-- INACTIVATION
*UNICELLULAR ALGAE-- BIOLOGICAL RADIATION EFFECTS
560131* --Biomedical Sciences
Applied Studies--Radiation Effects--Radiation Effects on Microorganisms--Basic Studies
IRRADIATION
N48310* --Life Sciences--Radiation Effects on Microorganisms- -Basic Studies
NITRATES
OXYGEN
REDUCTION
X RADIATION