ANNUAL REPORT - Department of Biotechnology

Cross Sectional Morphology of the TPHSM Impregnated Collagen
delivery device is one such class of new generation
wound dressing.
Drug Development
Investigations on programmed cell death in
pathogenic bacteria: towards developing novel
antibiotics to control infectious diseases were carried
out at JNU, New Delhi. The organism under study,
Bacillus anthracis, is a pathogen that causes deadly
anthrax disease in cattle and humans. Through
extensive database mining and BLAST search, a
Toxin-Antitoxin module has been hypothesized in B.
anthracis chromosomal DNA where it exists as an
operon and was found to be 50% homologous to E.
coli. The toxin is reported to belong to a family of
PemK like toxins (116 amino acid residues) while the
antitoxin (95 amino acid residues) is not well defined
in the database. The genetic organization of toxinantitoxin
loci led the investigation to infer the
presence of second ORF upstream from the PemK
DBT Annual Report 2006-07
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homolog of B. anthracis.
Drug Delivery
Studies on drug delivery system targeting of antileishmanial
drugs to specific sites using lipid
microspheres were carried out at Kakatiya University,
Warangal & IICB, Kolkata. The pharmacokinetic
parameters of Amphotericin B in rats and mice were
influenced by the type of lipid microspheres
formulation administered. Pegylated lipid
microspheres exhibited higher mean residence time
while mannose grafted and positively charged
systems cleared quickly due to rapid tissue
distribution. Tissue distribution studies revealed the
facts that both the mannose grafted lipid
microspheres and positively charged lipid
microsphers are concentrated in liver and spleen
where the leishmania parasite resides. This is in
conformity with the results obtained in in vivo antileishmanial
studies. The nephrotoxicity observed is
due to high Amphotericin B levels in kidneys following
fungizone administration. Amphotericin B distribution
to kidney and brain has not been influenced much by
the type of formulation administered. The
pharmacokinetic parameters obtained both in rats
and mice with piperine followed similar pattern. The
clearance was very high for free piperine as
compared to those obtained following the
administration of formulations. The tissue distribution
pattern of piperine following the IV administration of
free piperine and lipid microspheres formulations is
similar to that of Amphotericin B indicating the strong
influence of the characters of the lipid microspheres
on drug distribution.
Acanthamoeba
Studies continued on in vitro pathogenicity, molecular
characterization and molecular diagnosis of
Acanthamoeba infections at LVPEI & CCMB,
Hyderabad. Results of the assay done on clinical
samples from test and control subjects were found to
have a sensitivity of >85.0% with some of the
smear/culture positive samples failing to amplify the
Acanthamoeba specific amplicons.