Biomaterial Database

Characterization of the hybridization between purified 16S and 23S ribosomal ribonucleic acid and ribosomal deoxyribonucleic acid from Escherichia coli. 1976

P P Dennis, and D H Nordan

An assay to distinguish specifically between 16S and 23S ribosomal ribonucleic acid (rRNA) has been developed. The assay involves hybridization of radioactive rRNA to deoxyribonucleic acid (DNA) from lambdailv5 transducing phage, which carries an rRNA transcription unit. Radioactive 16S or 23S rRNA can be specifically and completely competed from hybrids by using highly purified nonradioactive 16S or 23S competitor RNA, respectively. The preparation and purification of 16S rRNA and 23S rRNA are described in detail. The hybridization assay is extremely sensitive and efficient; 65 to 70% or more of the input radioactivity hybridizes to specific DNA in the absence of homologous competitor RNA, and at saturation virtually all of the specific DNA sequences are hybridized to rRNA. The results indicate that: (i) the 16S rRNA and 23S rRNA prepared as described are greater than 99% pure, (ii) 16S RRNA and 23S rRNA hybridize with equal efficiency and in equal molar amounts of lambdailv5 DNA; (iii) at saturation, about one molecule of 16S and one molecule of 23S rRNA are hybridized per genome equivalent of lambda ilv 5 DNA; (iv) essentially no cross-hybridization occurs between 16S and 23S rRNA; and (v) the sequence homology between 16S and 23S rRNA is negligible.

UI	MeSH Term	Description	Entries
D009693	Nucleic Acid Hybridization	Widely used technique which exploits the ability of complementary sequences in single-stranded DNAs or RNAs to pair with each other to form a double helix. Hybridization can take place between two complimentary DNA sequences, between a single-stranded DNA and a complementary RNA, or between two RNA sequences. The technique is used to detect and isolate specific sequences, measure homology, or define other characteristics of one or both strands. (Kendrew, Encyclopedia of Molecular Biology, 1994, p503)	Genomic Hybridization,Acid Hybridization, Nucleic,Acid Hybridizations, Nucleic,Genomic Hybridizations,Hybridization, Genomic,Hybridization, Nucleic Acid,Hybridizations, Genomic,Hybridizations, Nucleic Acid,Nucleic Acid Hybridizations
D003090	Coliphages	Viruses whose host is Escherichia coli.	Escherichia coli Phages,Coliphage,Escherichia coli Phage,Phage, Escherichia coli,Phages, Escherichia coli
D004269	DNA, Bacterial	Deoxyribonucleic acid that makes up the genetic material of bacteria.	Bacterial DNA
D004926	Escherichia coli	A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.	Alkalescens-Dispar Group,Bacillus coli,Bacterium coli,Bacterium coli commune,Diffusely Adherent Escherichia coli,E coli,EAggEC,Enteroaggregative Escherichia coli,Enterococcus coli,Diffusely Adherent E. coli,Enteroaggregative E. coli,Enteroinvasive E. coli,Enteroinvasive Escherichia coli
D012329	RNA, Bacterial	Ribonucleic acid in bacteria having regulatory and catalytic roles as well as involvement in protein synthesis.	Bacterial RNA
D012335	RNA, Ribosomal	The most abundant form of RNA. Together with proteins, it forms the ribosomes, playing a structural role and also a role in ribosomal binding of mRNA and tRNAs. Individual chains are conventionally designated by their sedimentation coefficients. In eukaryotes, four large chains exist, synthesized in the nucleolus and constituting about 50% of the ribosome. (Dorland, 28th ed)	Ribosomal RNA,15S RNA,RNA, 15S