Skip to main content

Table 3 Antibacterial activity of the immunized haemolymph and the purified mature defensin peptide on gram (-) and gram (+) bacteria.

From: Identification, phylogenetic analysis and expression profile of an anionic insect defensin gene, with antibacterial activity, from bacterial-challenged cotton leafworm, Spodoptera littoralis

Microorganism Antibacterial activity
(Gram stain) Immunized haemolymph Mature purified peptide
  24 h p.i. 48 h p.i. 24 h p.i. 48 h p.i.
Escherichia coli (-ve) ++ +++ + +++
Proteus vulgaris (-ve) + ++ (+) ++
Klebsiella pneumoniae (-ve) ++ +++ + ++
Staphylococcus aureus (+ve) +++ +++ ++ +++
Streptococcus sanguinis (+ve) +++ +++ +++ +++
  1. (+): Inhibition zone less than 1 mm surrounding the 6 mm paper disk
  2. +: Inhibition less than positive control
  3. ++: Inhibition comparable to positive control
  4. +++: Inhibition more than 10 mg penicillin; inhibition zones of references = 13 ± 1 mm diam.