Direct Colony Thin-Layer Chromatography and Rapid Characterization of Serratia marcescens Mutants Defective in Production of Wetting Agents

Abstract

A bacterial mass (ca. 1 mg) was placed directly on a thin-layer chromatography plate and developed shortly in chloroform-methanol (2:1, vol/vol). After being dried, the bacterial mass was developed in chloroformmethanol-5 M ammonia (80:25:4, vol/vol). The obtained chromatogram indicated the characteristic lipid compositions of the bacteria. So, it became possible to examine bacterial colonies at once for the identification of mutants defective in the production of specific lipids.

Serratia marcescens Gene Required for Surfactant Serrawettin W1 Production Encodes Putative Aminolipid Synthetase Belonging to Nonribosomal Peptide Synthetase Family

“…Harshey, Institute of Cellular and Molecular Biology, University of Texas at Austin, U.S.A., were described previously (11), and mini-Tn5 inserted mutants were obtained by using pUTmini-Tn5 Km1 as described previously (22). Screening for serrawettinless mutants was performed by the examination of wetting activity on a clean slide glass (12), and direct colony TLC (17). Luria-Bertani (LB) medium (11) was used routinely in the genetic experiments with plasmid host strains Escherichia coli JM109, S17-1 λpir, and SM10 λpir.…”

Two Pseudomonas aeruginosa clonal groups belonging to the PA14 clade are indigenous to the Churince system in Cuatro Ciénegas Coahuila, México

“…After centrifugation, the absorbance at 495 nm of the supernatant was measured with a spectrophotometer zeroed with a control reaction using LB medium alone. RL were measured as reported (Chandrasekaran and Bemiller, 1980) and were visualized by thin layer chromatography (Matsuyama et al, 1987).…”

Microbial surfactants and their use in field studies of soil remediation

“…Desai and Banat (1997) have reviewed a wide range of techniques to determine the presence of biosurfactants in culture media. The methods include colorimetric analyses for the detection of anionic surfactants (Shulga et al 1992) and rhamnolipids (Hansen et al 1993;Siegmund and Wagner 1991), Emulsification Index determination over a 24-h period (Cooper and Goldenberg 1987), drop-collapsing test (Jain et al 1991), direct TLC technique (Matsuyama et al 1991) and axisymmetric drop shape analysis (ADSA; Van der Vegt et al 1991). Extraction and purification of biosurfactants from culture media can then be identified structurally and compared to previously identified types using a range of techniques and surfactant type.…”