TableEdit
PMID:19377097
You don't have sufficient rights on this wiki to edit tables. Perhaps you need to log in. Changes you make in the Table editor will not be saved back to the wiki
See Help for Help on this wiki. See the documentation for how to use the table editor
| Citation |
Graham, AI, Hunt, S, Stokes, SL, Bramall, N, Bunch, J, Cox, AG, McLeod, CW and Poole, RK (2009) Severe zinc depletion of Escherichia coli: roles for high affinity zinc binding by ZinT, zinc transport and zinc-independent proteins. J. Biol. Chem. 284:18377-89 |
|---|---|
| Abstract |
Zinc ions play indispensable roles in biological chemistry. However, bacteria have an impressive ability to acquire Zn(2+) from the environment, making it exceptionally difficult to achieve Zn(2+) deficiency, and so a comprehensive understanding of the importance of Zn(2+) has not been attained. Reduction of the Zn(2+) content of Escherichia coli growth medium to 60 nm or less is reported here for the first time, without recourse to chelators of poor specificity. Cells grown in Zn(2+)-deficient medium had a reduced growth rate and contained up to five times less cellular Zn(2+). To understand global responses to Zn(2+) deficiency, microarray analysis was conducted of cells grown under Zn(2+)-replete and Zn(2+)-depleted conditions in chemostat cultures. Nine genes were up-regulated more than 2-fold (p < 0.05) in cells from Zn(2+)-deficient chemostats, including zinT (yodA). zinT is shown to be regulated by Zur (zinc uptake regulator). A mutant lacking zinT displayed a growth defect and a 3-fold lowered cellular Zn(2+) level under Zn(2+) limitation. The purified ZinT protein possessed a single, high affinity metal-binding site that can accommodate Zn(2+) or Cd(2+). A further up-regulated gene, ykgM, is believed to encode a non-Zn(2+) finger-containing paralogue of the Zn(2+) finger ribosomal protein L31. The gene encoding the periplasmic Zn(2+)-binding protein znuA showed increased expression. During both batch and chemostat growth, cells "found" more Zn(2+) than was originally added to the culture, presumably because of leaching from the culture vessel. Zn(2+) elimination is shown to be a more precise method of depleting Zn(2+) than by using the chelator N,N,N',N'-tetrakis(2-pyridylmethyl)ethylenediamine. |
| Links |
PubMed PMC2709383 Online version:10.1074/jbc.M109.001503 |
| Keywords |
Binding Sites; Binding, Competitive/physiology; Biological Transport/physiology; Escherichia coli/genetics; Escherichia coli/growth & development; Escherichia coli/metabolism; Escherichia coli Proteins/chemistry; Escherichia coli Proteins/genetics; Escherichia coli Proteins/metabolism; Fluorescent Dyes/metabolism; Fura-2/analogs & derivatives; Fura-2/metabolism; Gene Expression Profiling; Gene Expression Regulation, Bacterial/physiology; Microbiological Techniques; Oligonucleotide Array Sequence Analysis; Protein Structure, Tertiary; Ribosomal Proteins/chemistry; Ribosomal Proteins/genetics; Ribosomal Proteins/metabolism; Zinc/deficiency; Zinc/metabolism |
| public |
| Cancel |
