Filamentous bacteriophage stability in non-aqueous media

Background: Filamentous bacteriophage are used as general cloning vectors a s well as phage display vectors in order to study li.-and-receptor interact ions. Exposure to biphasic chloroform-water interface leads to specific con traction of phage, to noninfective I- or S-forms. Results: Upon exposure. phage were inactivated (non-infective) at methanol, ethanol and I-propanol concentrations inversely dependent upon alcohol hyd rophobicity. Infectivity loss of phage at certain concentrations of I-propa nol or ethanol coincided with changes in the spectral properties of the fl virion in ultraviolet fluorescence and circular dichroism studies. Conclusions: The alcohols inactivate filamentous phage by a general mechani sm - solvation of coat protein - thereby disrupting the capsid in a manner quite different from the previously reported I- and S-forms. The infectivit y retention of phagemid pG8H6 in 99% acetonitrile and the relatively high g eneral solvent resistance of the phage strains studied here open up the pos sibility of employing phage display in non-aqueous media. (C) 2001 Elsevier Science Ltd. All rights reserved.