Book of Abstracts (PDF) - International Mycological Association

IMC7 Main Congress Theme V: CELL BIOLOGY AND PHYSIOLOGY Posters
sterile elements occur before the formation of mature
basidium. The process of cell senescence and death in B
(Aphyllophorales) occur in the direction from the trama of
pileus to trama hymenophore and subhymenium. In FB of
Agaricales and Gasteromycetes this processes occur in
direction, from the base of stipe to its upper part, later they
occupied the trama of pileus, trama pf hymenophore and
subhymenium. It was supposed that during the
morphogenesis of B and FB in Holobasidiomycetes they
are early transforming in to the autonomous from
mycelium way of morphogenesis.
1186 - Construction of a gene-trap vector, pPTR-
EGFP1 and pUsCdelPA2, for Aspergillus oryzae
S. Suzuki * & Y. Kashiwagi
National Food Research Institute, Kan-nondai 2-1-12
Tukuba Ibaraki 305-8642, Japan. - E-mail:
satosuz@nfri.affrc.go.jp
A promoter-trap vector that uses GFP as a reporter for
Aspergillus oryzae gene expression and a polyA-trap vector
using auxotrophic selection marker were constructed for
the first time. The promoter-trap vector, pPTR-EGFP1, and
polyA-trap vector, pUsCdelPA2 can be used to investigate
unknown gene function. These gene-trap vector were
integrated into a host genome randomly and transformants
were selected by drug resistans or auxotrophic marker gene
on the vector. The endogenous promoter activity trapped
by the pPTR-EGFP1 vector was used to express the
reporter gene egfp. The endogenous polyA addtion signal
trapped by the pUsCdelPA2 vector was used to express the
auxotrophic marker gene sC on the vector. By the
transformation using pPTR-EGFP, approximately 300 drug
resistant transformants were obtained, one of which
showed the same strong fluorescence as GFP. The
expression of egfp gene was confirmed by Northern blot
analysis. The flanking genome regions of the integrate site
was isolated by plasmid rescue method. Our resuls show
that this newly constructed vector, pPTR-EGFP1, can trap
endogenous promoter activity. The transformation using
pUsCdelPA2 is under continuation now.
1187 - Production of CsmA, a class V chitin synthase
with a myosin motor-like domain of Aspergillus
nidulans, is regulated in multiple ways
N. Takeshita, A. Ohta & H. Horiuchi *
Department of Biotechnology, The University of Tokyo, 1-
1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan. - E-mail:
ahhoriu@mail.ecc.u-tokyo.ac.jp
Chitin, a β-1,4-linked homopolymer of Nacetylglucosamine
(GlcNAc), is one of the major structural
components of the fungal cell wall. Chitin synthases are
membrane-bound proteins and have been classified into
five groups, classes I to V, on the basis of the structures in
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Book of Abstracts
their conserved region. csmA gene of Aspergillus nidulans
encodes a class V chitin synthase with a myosin motor-like
domain at its N-terminus. csmA null mutants showed
remarkable abnormalities in polarized growth, hyphal wall
integrity, and conidiophore development. In this study, to
investigate the intracellular behavior of the csmA product
(CsmA) and the regulation of its production, we
constructed strains that produced CsmA tagged with nine
repeats of hemagglutinin A (HA) epitope at its C-terminus,
CsmA-HA, instead of CsmA. Western blot analysis with
anti-HA antibody proved that the entire coding region of
csmA was translated as a single polypeptide with an
approximate molecular mass of 210 kDa. CsmA-HA was
found in the membrane fraction of the CsmA-HA
producing strain. CsmA-HA was produced during
vegetative growth, and its amount increased under low
osmotic conditions. A discrepancy in the amounts of
CsmA-HA protein and csmA transcript as determined by
northern analysis under those conditions suggests that the
production of CsmA is regulated at both the transcriptional
and post-transcriptional levels.
1188 - Media optimization for manganese peroxidase
production by response surface methodology in a newly
isolated white-rot fungus Trichophyton rubrum LSK-27
C. Tamerler 1* , U.O.S. Seker 1 , K. Li 3 , H. Jung 2 & H.
Bermek 1
1 Istanbul Technical University, Molecular Biology and
Genetics, Maslak - Istanbul 80626, Turkey. - 2 Sunchon
National University, Department of Forest Resources,
Sunchon 540-742, Korea. - 3 Oregon State University,
Department of Wood Science and Engineering, 102
Richardson Hall, Corvallis, OR97331-5751, U.S.A. - Email:
tamerler@itu.edu.tr
Response surface methodology (RSM) is a useful
technique for media optimization, which is a crucial step
for maximizing enzyme production in fungal cultures. In
current study, RSM was applied for media optimization in
a newly isolated white rot-fungus T. rubrum LSK-27, for
manganese peroxidase (MnP) production. Carbon, nitrogen
and also phosphorus are known to have significant impact
in the production of fungal enzymes. Manganese stimulates
MnP production in most fungi. In the first optimization
step, glucose (x1), mycological peptone (x 2), MnSO 4 (x 3)
and KH 2PO 4 (x 4) were studied to investigate their effect on
MnP production by fractional factorial design, 2 4_1 . The
first order equation with the regression coefficients were
computed to be y=0.7175+0.0625x 1+0.4318x 2-0.1201x 3-
0.0364x 4 with a probability level of 91% for MnP
production. Although glucose and KH2PO 4 positively
affected the cell growth, they did not increase the enzyme
levels. Among the response curves obtained for four media
components, the highest response was obtained for
MnSO4-peptone pair, which was chosen as main factors for
central composite design. Effect of each media ingredient
on fungal morphology was also followed. The optimum
MnSO 4-peptone concentrations were found for maximum
MnP production.