(1) The resulting vector, pHSG683, confers chloramphenicol resistance, enforces SmS on strAR and supE- host bacteria, and has multiple cloning sites within the coding region of synthetic rpsL gene.
(2) When pHSG683 DNA was prepared from strAR and sup+ cells grown in tryptophan-rich medium with Cm and Sm, less than 10(-6) plasmids failed to enforce SmS on strAR and supE- cells in tryptophan-less medium with Cm.
(3) The lung volume at which airway closure occurred in pregnancy and the post-partum period did not change in relation to the vital capacity whereas the expiratory reserve volume did, so that airway closure became imminent in the pregnant women during tidal ventilation, especially whilst in the suping position.
(4) We show here that the mutation in rodA is a single-base change from a glutamine to a chain termination (amber) codon, and that an amber suppressor (supE) present in the strain restores the ability to produce a reduced level of normal RodA protein.
(5) The lethal phenotype was expressed specifically in supE (glutamine-inserting) host strains and not in Sup+ strains, because the mutant genes, by design, also possessed an amber mutation derived from a glutamine codon.
(6) About 90% of the Trp+ revertants induced by methylnitrosocyanamide were due to mutations in suppressor genes, and 85% of the suppressor mutations occurred in gene supE.
(7) This can be eliminated by using a supE-strain as MG1655 and by site-directed mutagenesis of the cDNA to create an in frame UAA stop codon.
(8) All three mischarging mutant enzymes still retain a certain degree of tRNA specificity; in vivo they acylate supE glutaminyl tRNA (tRNA(Gln] and supF tRNA(Tyr) but not a number of other suppressor tRNA's.
(9) The asuA1 and asuA2 mutations are linked to trp, reduce suppression by supE approximately twofold, and affect a variety of suppressors.
(10) When amber suppressor mutations at the supD, supE, or supF loci were introduced into such sup0 osmodefective strains, they became osmotolerant and gained the ability to accumulate trehalose in response to elevated medium osmolarity.
(11) The two independently isolated suppressors behaved as supD and supE mutants, respectively, of E. coli.
(12) High levels of expression of I-FABP mRNA in supE+ strains of E. coli, such as JM101, is associated with suppression of termination at its UGA stop codon.
(13) Our results indicate that the supE glutamine tRNA context can tolerate multiple mutations (including mutation of the discriminator and first base-pair) and still remain predominantly glutamine-accepting.
(14) Of the 15 mutants generated by this method, none are suppressible by supD, supE, or supF.
(15) The effects of streptomycin and neomycin on the phenotypic suppression of frameshift mutations in the lacZ gene of Escherichia coli and on the efficiency of suppression of amber mutations in T4 phage by the informational supE tRNA nonsense suppressor were compared.
(16) Suppressor analysis by using BE1047 (trpambphooch) revealed that the most frequently occurring reversion was due to a mutation in suppressor gene, supE.
(17) Plaque-forming phages carrying the E. coli trp, his, cysB, thyA, supD, supE, sup F, hsd, tna and lig genes have been isolated.
(18) Or perhaps Aquaman could pop his head unexpectedly above the waterline and reveal the existence of a previously unimagined submerged society of mer-men while Supes is having a quiet day off fishing.
(19) Phage of the insertion mutant, M13mp19-NheI, produced light blue plaques on SupE strains because of the introduced amber codon.
(20) In all three, the relaxed phenotype was suppressed by supD, supE, supF or sup6.