MICB 201 Lecture Notes - Lecture 9: Motility, Coevolution, Plant Virus
Document Summary
Chapter 4: antibiotics and antibiotic resistance in bacteria (continued) Almost any kind of gene is subject to hgt. There are several types of antibiotic resistance genes. Asso(cid:272)iated (cid:449)ith the uptake of (cid:862)(cid:374)aked(cid:863) dna fro(cid:373) the e(cid:374)(cid:448)iro(cid:374)(cid:373)e(cid:374)t. Donor dna: naked dna in environment, comes from organisms that die and lyse, the donor: dead! Competence: recipient has to be in a physiological state called (cid:862)competent state(cid:863) to tra(cid:374)sport. Dna: (cid:862)com(cid:863) proteins proteins required for dna transport synthesized by competent organisms, development of competence poorly understood, reproducing on laboratory nutrient media, some bacteria: Always competent = constitutive com gene expression. Become competent only under specific environmental conditions = environmentally-controlled com gene expression (conditions vary with organism) Dna binding and transport: the gram-negative cell wall: same process as in gm +ve except additional protein involved because of om, proteins named differently. Some species: bind/transport dna only of close relatives: (cid:862)re(cid:272)og(cid:374)ize(cid:863) their (cid:272)lose relati(cid:448)es (cid:271)y prese(cid:374)(cid:272)e of a particular nucleotide sequence in.
