Abstract:
The use of genetically engineered probiotics to exp
ress specific enzymes has been the
subject of considerable attention in poultry indust
ry because of increased nutrient
availability and reduced cost of enzyme supplementa
tion. Phytase enzyme is commonly
added to poultry feed to improve digestibility and
availability of phosphorus from plant
sources. To construct a probiotic with potential of
phytate degradation,
phytase
gene
(appA) from
E. coli
was cloned and transformed into two probiotic bact
eria
Lactobacillus
salivarius
and
Lactococcus lactis
. The results showed plasmid instability, unable to
express
the gene. The expression of
appA
gene in
L. lactis
was analyzed by detecting specific RNA
and zymography assay. Phytase enzyme was isolated f
rom cellular extracts of
recombinant
L. lactis,
showing a 46 kDa band upon the SDS-PAGE analysis. Z
ymogram
also confirmed the phytase activity of the 46 kDa b
and corresponding to the enzyme. An
enzyme activity of 4.9 U mL
-1
was obtained in cell extracts of
L. lactis
. The growth of
native and recombinant
L. lactis
was similar in the presence of two concentrations
of ox
bile.
Keywords
:
Lactobacillus salivarus
,
Lactococcus lactis
, Recombinant, Phytase, Poultry
