Studies of the effects of ultraviolet radiation on the structural integrities of ribosomal RNA components of the Escherichia coli 50S ribosomal subunit

Journal Article · Tue Jul 25 04:00:00 EDT 1978 · Biochemistry; (United States)

DOI:https://doi.org/10.1021/bi00608a033· OSTI ID:6677978

Gorelic, L; Parker, D

The effects of 254-nm radiation on the structural integrities of free and 50S ribosome-bound 5S and 23S ribosomal ribonucleic acids (rRNA) have been elucidated. Irradiation of aqueous solutions of Escherichia coli 50S ribosomes with 253.7-nm radiation results in the formation of single-strand breaks in double-stranded regions of the 23S rRNA component, but not in rRNA chain scission, and destabilization of the secondary structure of the 23S rRNA toward denaturation. The minimum doses of 253.7-nm radiation required for the first detection of the two effects are 7 x 10/sup 19/ quanta for the production of single-strand breaks in double-stranded regions of the 23S rRNA, and< or = to 2.3 x 10/sup 19/ quanta for destabilization of the 23S rRNA secondary structure. Free 23S rRNA is resistant toward photoinduced chain breakage at doses of 253.7-nm radiation up to at least 2.3 x 10/sup 20/ and is much less sensitive toward destabilization of secondary structure than ribosome-bound 23S rRNA. In contrast to the photosensitivity of 50S ribosome-bound 23S rRNA toward chain breakage, 50S ribosome-bound 5S rRNA is resistant toward chain breakage at doses of 253.7-nm radiation up to at least 2.3 x 10/sup 20/ quanta. Ribosome-bound 5S and 23S rRNA are also not photosensitive toward intermolecular 5S/23S rRNA cross-linkage.

• Research Organization: Wayne State Univ., Detroit
• OSTI ID: 6677978
• Journal Information: Biochemistry; (United States), Journal Name: Biochemistry; (United States) Vol. 17:15; ISSN BICHA
• Country of Publication: United States
• Language: English

Related Subjects

550200 -- Biochemistry
550701 -- Microbiology-- Tracer Techniques
560111* -- Radiation Effects on Biochemicals-- In Vitro-- (-1987)
59 BASIC BIOLOGICAL SCIENCES
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
BACTERIA
BIOLOGICAL EFFECTS
BIOLOGICAL RADIATION EFFECTS
CELL CONSTITUENTS
DISPERSIONS
ELECTROMAGNETIC RADIATION
ESCHERICHIA COLI
IN VITRO
IRRADIATION
MICROORGANISMS
MIXTURES
MOLECULAR STRUCTURE
NUCLEIC ACIDS
ORGANIC COMPOUNDS
ORGANOIDS
RADIATION EFFECTS
RADIATIONS
RADIOINDUCTION
RADIOSENSITIVITY
RIBOSOMES
RNA
SOLUTIONS
STRAND BREAKS
ULTRAVIOLET RADIATION