| 摘要 |
New bacteria (A) with better resistance to stress than the wild type has /- 1 mutation in a gene (I) that alters the normal activity of (I), or of some other gene in the same transcription unit. (I) is involved in transport of electrons, amino acids, oligopeptides or phosphate, in DNA repair, stability of RNA or are new genes, and they are (a) genes involved in biosynthesis of guanosine phosphates (GP) or (b) genes of the clones R1.1 (pstS); R1.4 (arl1); R1.5 (glnP); R1.7 (carB); R1.8 (glnP); R1.14 (arl2); R1.16 (glnP); R1.17 (glnQ); R1.20 (arl3); R2.6 (pstB); R2.9 (recN); R2.11 (arl4); R2.15 (arl5); R2.17 (arl7); R2.20 (arl8, yybT); pstS, pnpA and trl1. Genes involved in GP synthesis are deoB, hpt, guaA, relA/spoT and tktA. The specification includes > 70 sequences of mutated genes that confer increased stress resistance. Mutation of (I) is (a) by insertion/deletion of a DNA sequence by recombination (preferably using a mobile genetic element, particularly in plasmid pGh:ISS1); (b) treatment with mutagen or (c) by spontaneous mutation. Where DNA is inserted, this is preferably from the same species as the cells being altered. Mutations preferably inactivate, or modulate expression of, (I), or of some other gene in the transcription unit. |
