In this report

the chemotaxis properties of an oil-degrading strain 6-1B using the swarm plate assay and the characteristics of chemotaxis movement towards crude oil are described.The strain 6-1B

isolated from formation water samples from Daqing Oilfield

China

was determined as Pseudomonas sp.(99.9% identity)by 16S rDNA sequence analysis and physiological and biochemical characteristics.The organism was shown to utilize crude oil as the sole carbon and energy source.Cell growth and crude oil degradation occurred at 42℃.As many natural isolates of Pseudomonas sp.

strain 6-1B was highly motile with a polar flagella and was found to be chemotactic towards a variety of metabolites including glycine

glycerol and sucrose.Moreover

chemotaxis was also observed towards crude oil and n-alkenes such as tridecane.The maximum chemotaxis rate was 35 μm·s -1

while the maximum bacterial concentration occurred in the oil-water interface.