ao7b00181_si_001.pdf (1.17 MB)
Side-Chain Amino Acid-Based Cationic Antibacterial Polymers: Investigating the Morphological Switching of a Polymer-Treated Bacterial Cell
journal contribution
posted on 2017-04-25, 08:15 authored by Ishita Mukherjee, Anwesha Ghosh, Punyasloke Bhadury, Priyadarsi DeSynthetic polymer-based antimicrobial
materials destroy conventional
antibiotic resistant microorganisms. Although these antibacterial
polymers imitate the properties of antimicrobial peptides (AMPs),
their effect on bacterial cell morphology has not been studied in
detail. To investigate the morphology change of a bacterial cell in
the presence of antimicrobial polymer, herein we have designed and
synthesized side-chain amino acid-based cationic polymers, which showed
efficient antibacterial activity against Gram-negative (Escherichia coli), as well as Gram-positive (Bacillus subtilis) bacteria. Morphological switching
from a rod shape to a spherical shape of E. coli cells was observed by field emission-scanning electron microscopy
analysis due to cell wall disruption, whereas the B.
subtilis cell structure and size remained intact,
but stacks of the cells formed after polymer treatment. The zone of
inhibition experiment on an agar plate for E. coli cells exhibited drastic morphological changes at the vicinity of
the polymer-treated portion and somewhat less of an effect at the
periphery of the plate.