Amber mutation

Figure 1. The frequencies of amber mutations in the lacl gene induced by BPDE. Solid bars, individual sites at which we detected mutations open bars, sites at which we did not detect mutations asterisks (in a), sites at which the target codon contains 5-methylcytosine.

Kitamoto, T., Iizuka, R., and Tateishi.J. (1993). An amber mutation of prion protein in Gerstmann-Straussler syndrome with mutant PrP plaques. Biochem. Biophys. Res. Commun. 192, 525—531. 

T Inada, DL Court, K Ito, Y Nakamura. Conditionally lethal amber mutations in the leader peptidase gene of Escherichia coli. J Bacteriol 171 585-587, 1989. 

The fraD36 mutation (Achtman et al., 1971) permits, under current NIH and GMAG guidelines, the containment conditions to be dropped by one category. M13mp7 also contains two amber mutations. 

Noren CJ, Anthony-Cahill SJ, Suich DJ, Noren KA, Griffith MC, Schultz PG. In vitro suppression of an amber mutation by a... 

Atweh GF, Brickner HE, Zhu X-X, Kazazian HHJ, Forget BG New amber mutation in a b-thalassemic gene with nonmeasurable levels of mutant messenger RNA in vivo. J Clin Invest 82 557-561,1988. 

A number of triplets are referred to as nonsense codons because they are not known to code for any specific amino acid. When bacterial strains were developed in which mutations leading to the appearance of such triplets in their messenger were produced, 3 of the so-called nonsense codons, UAG, UGA (amber mutation), and UAA (ocre mutation) were found to act as punctuation codons for termination of the chain. 

The safety (or biological containment) of these phage vectors have also been increased by introduction of amber mutations so that they require suppressor strains of E. coli as hosts. 

Mutation in 30S ribosomal subunit protein S12. It confers resistance to streptomycin. Also written str A Amber mutation which prevents lysis of the infected or expression-induced cells that lack the amber suppressor supF Also denoted as SI00. See Sam7... 

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