Letno poročilo 2005

encima je sposobnost aktivacije ob prisotnosti
specifi~nih celi~nih aktivatorjev, medtem ko je
rezistenten na inhibicijo s citratom. O
posttranslacijski modifikaciji 6-fosfofrukto-1kinaze,
tega klju~nega regulatornega encima
glikolize, smo objavili ~lanek v ugledni
znanstveni reviji. Pripravili smo skraj{an gen,
ki je po transformaciji v glivine celice
neposredno sintetiziral kraj{i fragment.
Transformanti gliv A. niger in A. terreus, ki so
nosili integriran gen za kraj{i fragment, so bili
sposobni hitrej{e sinteze kon~nih produktov.
Pozitivni efekt vnosa gena za kraj{i fragment
se je pokazal tudi pri produkciji heterolognih
proteinov pri kvasovki Pichia pastoris. Zaradi
izredne uporabne vrednosti rezultatov
pridobljenih s projektom ANTICO, se je
konzorcij raziskovalcev iz petih evropskih
in{titucij odlo~il, da bo izsledke patentno
za{~itil. Isto~asno se pripravljamo tudi na
navezavo stikov z uporabniki iz razli~nih,
primarno evropskih biotehnolo{kih dru`b, s
katerimi nameravamo za~eti pogovore o
licenciranju.
Pri glivi Aspergillus niger smo lo~ili dva
izoencima NADP-odvisne izocitrat dehidrogenaze.
Encima imata razli~ne kineti~ne
lastnosti in razli~no lokacijo v celici. Med
izoencimoma so izrazite razlike v velikosti in
stopnji aktivacije ter stopnji inhibicije ob
prisotnosti razli~nih metabolitov.
SLIKA 1:
Gram-negativna bakterija Escherichia coli, kateri je
bil na desni sliki dodan antimikrobni peptid, ki
povzro~i opazne po{kodbe bakterijske celi~ne stene.
Sliko sta z elektronskim mikroskopom na Kemijskem
in{titutu posneli Lorena Butinar in Mateja Zorko.
Laboratorij za biotehnologijo
Laboratory of Biotechnology
fragment of the enzyme with a changed kinetics.
The essential advantage of the new form
of enzyme was the ability of activation in the
presence of specific cell activators, while it was
resistant to inhibition by citrate. About the
posttranslational modification of PFK1, the key
regulatory enzyme in glycolysis, we reported in
a publication in a recognized international journal.
We prepared a shortened gene that directly
synthesized the shorter fragment after transformation
into fungal cells. The transformants
of A. niger and A. terreus having the integrated
gene for the shorter fragment were able to synthesize
the final products in shorter time. The
positive effect of the introduction of the gene
for the shorter fragment was evident also in
the production of heterologuos proteins in the
yeast Pichia pastoris. Due to the outstanding
applicability of the results obtained in the
ANTICO project the consortium decided to patent
the findings. At the same time we have
contacts with the potential users, such as European
biotechnological companies, to discuss
about licensing.
With the fungus A. niger two iso-enzymes of
NADP-dependent iso-citrate dehydrogenase
were separated. The iso-enzymes have different
kinetic characteristics and different location
within the cell. Between them there are pronounced
distinctions in their sizes and in their
FIGURE 1:
Electron micrograph of Gram-negative bacteria Escherichia
coli. Antimicrobial peptide has been added
to the bacteria on the right panel. Large defects in
the cell membrane is visible. SEM pictures were made
on the instrument at the National Institute of Chemistry
by Lorena Butinar and Mateja Zorko.
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