TABLE 1.

Phenotypes of Methylobacterium sp. strain CM4 chloromethane utilization-negative mutants

Strain	Growth substratea	Production of chloride:		Presence of chloromethane-induced proteins on SDS-PAGEc:		DNA restriction fragments (kb) on Southern blotting withd:
		During growth	In resting cells (μmol/min/mg of protein)b	65 kDa	35 kDa	ClaI	KpnI
Wild type	CM	+	1.16	+++	+++	−	−
Wild type	MA	−	<0.05	−	−	−	−
Wild type	MA-CM	+	0.29	+	+++	−	−
Group 1 mutants
19D10	MA-CM	−	<0.05	+	+++	3.9	7.8
22B3	MA-CM	−	<0.05	−	+++	8.2	7.1
38A10	MA-CM	−	<0.05	−	+++	8.2	7.1
27C10	MA-CM	−	<0.05	−	+++	12.4	11.7
Group 2 mutants
36D3	MA-CM	+	0.86	+	+++	4.2	7.8
30F5	MA-CM	+	0.32	+	−	8.2	6.9
38G12	MA-CM	+	0.37	+	−	8.2	6.9
27B11	MA-CM	+	0.67	+	+++	12.4	12.4
11G7	MA-CM	+	0.28	+	+++	9.9	15.7

^aNone of the mutants grew with chloromethane (CM) as the sole growth substrate. MA, methanol. 

^bAverage of triplicate runs. 

^c+++, CM-grown wild-type levels; +, MA-CM-grown wild-type levels; −, not detectable. 

^dProbes were synthesized from MiniTn5Km sequence.