TABLE 2.

Characterization of numerically dominant, culturable PAH degraders in the bioremediated soil used as an inoculum

PAH used for isolation	Isolate	GenBank accession no.	Closest relative based on partial 16S rRNA gene sequence (% homology)	Growth on PAHs, determined as reduction of WST-1 (A450-630)a
				Hex	Phe	Fla	Pyr
Phe	Ri456a	EF012722	Arthrobacter oxydans (99.8)	0.01	0.86	0.01	0.01
Phe	Ri463b	EF012740	M. frederiksbergense (99.8)	0.27	1.69	0.22	1.62
Phe	Ri452b	EF012741	M. austroafricanum (97.6)	0.07	1.66	0.06	0.52
Phe	Ri465a	EF012742	M. austroafricanum (100)	0.05	0.79	0.10	0.35
Phe	Ri455	EF012743	M. gilvum (99.7)	0.07	2.04	0.01	0.48
Phe	Ri457	EF012744	M. gilvum (100)	0.03	0.73	0.01	0.31
Phe	Ri469	EF185792	M. aurum (99.8)	0.24	1.22	0.24	0.36
Phe	Ri464	EF012746	M. aurum (100)	0.17	1.36	0.43	0.63
Phe	Ri458a	EF012747	M. vaccae (100)	0.02	0.57	0.11	0.18
Phe	Ri460	EF012723	M. vaccae (100)	0.04	0.61	0.50	0.39
Phe	Ri466	EF012725	M. vaccae (99.5)	0.07	1.36	0.84	1.18
Pyr	Ri483a	EF012726	M. aurum (100)	0.09	0.56	0.09	0.26
Pyr	Ri477	EF012727	M. frederiksbergense (99.5)	0.31	2.07	0.20	1.67
Pyr	Ri470a	EF012728	M. gilvum (99.8)	0.03	1.14	0.02	0.26
Pyr	Ri484b	EF012729	M. gilvum (99.8)	0.12	0.73	0.10	0.54
Pyr	Ri481b	EF012730	M. gilvum (100)	0.03	1.09	0.02	0.26
Pyr	Ri489	EF012731	M. gilvum (100)	0.10	0.77	0.12	0.46
Pyr	Ri471c	EF012724	M. vaccae (99.8)	0.02	0.44	0.18	0.26
Pyr	Ri486ba	EF012732	M. vaccae (99.8)	0.03	0.59	0.19	0.29
Pyr	Ri487	EF012733	M. vaccae (99.4)	0.01	0.24	0.07	0.20
Fla	Ri505b	EF012734	M. pyrenivorans (99.8)	0.01	0.01	0.05	0.01
Fla	Ri506	EF012735	M. pyrenivorans (99.8)	0.05	0.05	0.34	0.05
Fla	Ri488a	EF012736	M. aurum (100)	0.14	0.07	0.37	0.14
Fla	Ri494	EF012737	M. aurum (100)	0.02	0.00	0.49	0.03
Fla	Ri495	EF012738	M. aurum (100)	0.07	0.02	0.18	0.03
Fla	Ri496	EF012739	M. vaccae (100)	0.08	0.74	0.26	0.23

^aNumbers in bold are significantly higher than those for the hexane control (one-sided t test, P < 0.05; n = 3). Phe, phenanthrene; Pyr, pyrene; Fla, fluoranthene; Hex, hexane control.