Screening marine fungi for plasmids and characterization of a linear mitochondrial plasmid in aLulworthiasp.

Abstract

Twenty-one marine filamentous fungi, in? cluding 18 isolates capable of growth on hexadecane, were screened for plasmids. Twenty of the isolates screened did not have plasmids, indicating that nei? ther the ability to grow on hydrocarbons nor the lack of this ability can be correlated with the presence of plasmids. One organism, Lulworthia sp. 046, that grows on hydrocarbons, contained a plasmid approx? imately 14kb in size. The plasmid, designated pQB, is linear, as shown by the results of both UV-nicking experiments and digestion with exonuclease III and lambda exonuclease. The plasmid was present in DNA extracted from mitochondria, and it banded with mitochondrial DNA when nuclear and mito?