Background and objective: Burkholderia pseudomallei
is a pathogenic bacterium, causing melioidosis, a
serious infectious disease. Currently, the best
treatment is using antibiotic drugs. However, many
clinical strains are now intrinsically resistant to almost
all available antibiotic drugs. Previous study indicated
that Bacillus amyloliquefaciens KKU14 strongly
inhibits B. pseudomallei. In this study, antimicrobial
peptide LcI of B. amyloliquefaciens KKU14 was cloned
and expressed to test activity against B. pseudomallei.
Materials and Methods: Antimicrobial peptide LcI
was searched from GenPept database (NCBI) and
amplified from genome of B. amyloliquefaciens KKU14
by PCR and cloned into different cloning vectors. The
recombinant clones were induced and their activity
against B. pseudomallei strain P37 were tested by agar
well diffusion and in-gel overlay.
Results: The recombinant peptide was successfully
cloned. However, the expression could be observed
only in pQE31 vector. The expressed peptide has the
size of approximately 10 kDa. Nevertheless, the
recombinant clones exposed no antimicrobial activities against B. pseudomallei strain P37.
Conclusion: The recombinant peptide LcI cloned
from B. amyloliquefaciens KKU14 does not inhibit B.
pseudomallei strain P37 in this study. This might due
to improper folding of the recombinant peptide, or
the peptide that was responsible for inhibition of B.
pseudomallei might be other peptides, or the inhibition
effect might need synergistically work from
several peptides together, which has to be further
investigated.