High-level chromate resistance in Arthrobactersp. strain FB24 requires previously uncharacterized accessory genes

Table 2 Specificity of Induction of Chromate Resistance Genes^a.

Gene	Cr(VI) 5 mM	Lead 5 μM^b	Arsenate 5 mM^c	H₂O₂ 5 mM^c
*chrL*	63.4 (29.7)	0.3 (0.02)	0.6 (0.05)	12.5 (3.50)
*chrA* ₆	50.7 (14.5)	0.2 (0.02)	0.8 (0.15)	3.2 (0.87)
*chrB-Cterm2*	6.3 (1.9)	0.1 (0.01)	0.3 (0.03)	0.1 (0.01)
*SCHR*	6.8 (1.9)	0.1 (0.01)	0.3 (0.03)	0.9 (0.12)
*chrK*	7.2 (1.6)	0.1 (0.01)	0.2 (0.04)	1.0 (0.21)
*chrB-Nterm*	16.9 (7.1)	0.1 (0.01)	0.4 (0.08)	0.5 (0.12)
*chrB-Cterm*	25.4 (4.4)	2.6 (0.12)	5.3 (0.97)	4.9 (0.70)
*chrJ*	92.4 (47.2)	0.7 (0.05)	1.7 (0.10)	6.6 (0.58)

^a Values shown for lead, arsenate and H₂O₂ represent the transcript copy number ng^-1 total RNA in each experimental condition relative to transcript levels in 0.2X NB and the SE (parentheses, n = 6 qRT-PCR reactions per treatment). The relative expression of each gene in 5 mM Cr(VI) is shown for comparison.
^b 0.5 and 50 μM lead also tested with similar results
^c 0.5 and 50 mM Arsenate and H₂O₂ also tested with similar results

ISSN: 1471-2180