TABLE 2.

Natural transformation and restoration of a 317-bp deleted nptII gene in Acinetobacter sp. strain BD413(pFG4) residing in sterile and nonsterile soil microcosms for 24 h, with added cell lysates of Acinetobacter sp., P. fluorescens, and B. cepacia^a

Cell lysate (chr::KTG) of:	Sterile soil			Nonsterile soil
	Mean no. of transformants (CFU) ± SDb	No. of transformants/recipient	No. of transformants/lysed cellc	Mean no. of transformants (CFU) ± SD	No. of transformants/recipient	No. of transformants/lysed cell
Acinetobacter sp. strain BD413	1,290 ± 146	7.4 × 10−6	5.6 × 10−6	44 ± 15	1.1 × 10−6	1.9 × 10−7
P. fluorescens R2F	77 ± 29	3.1 × 10−7	3.8 × 10−7	NDd	<1.4 × 10−8	<5.0 × 10−7
B. cepacia P2	334 ± 85	1.8 × 10−6	1.1 × 10−6	ND	<1.8 × 10−8	<3.1 × 10−7

^aFollowing 24 h of bacterial presence in soil, nutrients (5M9L25P) and lysates (after 1 h) were added, and the microcosms were incubated for 24 h at 20°C before plating and enumeration of CFU. 

^bThe mean coefficient of variation (SD/mean) of the CFU of transformants and recipients was between 0.3 and 0.4. 

^cThe number of lysed cells is the CFU count of the bacterial suspension used for preparation of the lysates. 

^dND, not detected.