. Isolation and partial characterization of Bacillus megaterium mutants deficient in poly-3-hydroxybutyrate synthesis

FLOCCARI, M.E., LÓPEZ, N.I., MÉNDEZ B.S., PIEPER-FÜRST, U., AND STEINBÜCHEL, A.

CANADIAN JOURNAL OF MICROBIOLOGY

Natl.Research Council

Año: 1995 vol. 41 p. 77 - 79

0008-4166

Poly (3-hydroxybutyrate) (PHB)-negative mutants of Bacillus megaterium were isolated following mutagenesis with N-mehyl-N´-nitrosoguanidine. Different strategies were used for isolation including ultracentrifugation through sucrose gradients and selection for resistance to allyl alcohol. The mutants were detected on agar plates by staining the colonies with Sudan Black. Four mutants did not synthesize any PHB as revealed by gas chromatographic analysis. The enzymatic characterization showed no or extremely low synthase activity for all of the mutants. In contrast, no significant alterations were observed in the ß-ketothiolase and the NADPH-dependent acetoacetyl-CoA reductase activities. All mutants sporulated in complete and minimal media.