Book of Abstracts (PDF) - International Mycological Association

IMC7 Main Congress Theme V: CELL BIOLOGY AND PHYSIOLOGY Posters
1128 - Nuclear NAD metabolism in fungi and yeast
A.M. Kerbalaeva * , S.M. Nasmetova, D.M. Ruzieva & T.G.
Gulyamova
Institute of Microbiology AS RU, A.Kadiry 7 B, Tashkent-
700128, Uzbekistan. - E-mail: imbasru@uzsci.net
Activity of NAD metabolism enzymes in nuclei at
stimulation of NAD production by F. sambucinum and S.
cerevisiae selected earlier as NAD-producers has been
studied. Cultivation of these fungi and yeast in the medium
containing 1 mM nicotinamide was accompanied by up to
3-fold increasing of intracellular NAD concentration in
steady state growth phase. The increasing of intracellular
NAD concentration accompanied by falling of its
intranuclear pool caused by acceleration of coenzyme
turnover due by growing up of nuclear NADpyrophosphorylase
and NAD-ase activites. Also we found
that the decreasing of nuclear concentration of NAD during
stimulation of its synthesis in cells by nicotinamide
correlates with its utilization at ADP-riboslylation of
nuclear proteins. It was detected that increasing of basal
and total ADP-ribosyl transferase activity attendant with
appropriate changes in the level of modification of nuclear
proreins as determined by the incorporation of 14 C -adenine
from NAD into fungi and yeast nuclei. Moreover, as it was
established by fractionation of nuclear proteins, although
80% radiolabel is localized in the fraction of histones, the
NAD content fluctuations mostly influences on the level of
ADP-ribosylation of nonhistone proteins. The conclusion
was made that ADP-rybosylation of nuclear proteins might
be one of the possible mechanisms of NAD oversynthesis
regulation in fungi and yeast.
1129 - Alkaline-tolerant fungi from Thailand: a source
for alkaline enzymes?
W. Kladwang 1* , A. Bhumiratana 2 , N.L. Hywel-Jones 1 & L.
Lange 3
1 BIOTEC, 73/1 Rama VI Rd. Radjhevee, Bangkok,
Thailand. - 2 Mahidol University, Rama VI Rd, Rajdhevee,
Bangkok, Thailand. - 3 Novozymes, Bagsvaerd 2880,
Denmark. - E-mail: wipapat@biotec.or.th
A collection of 490 isolates of alkaline-tolerant fungi was
established using PDA buffered at pH11. This was from
sand, soil, tree-holes and assorted plant material collected
from southern, central and northern Thailand. If possible
the sample pH was recorded and was between pH4 and 9.
Although alkaline habitats were good sources of alkalinetolerant
fungi it was significant that alkaline-tolerant fungi
could be isolated from samples that were pH4. Strains were
screened for their ability to hydrolyze arabinan, amylose,
potato-galactan and skimmed milk at pH10. Eleven genera
had activity against at least one of these substrates. Of
these 11, 7 were members of the Hypocreales.
Furthermore, of 57 positives, 51 belonged to the
Hypocreales and 38 were Acremonium/Stilbella spp.
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Book of Abstracts
Acremonium was therefore selected for further study.
Alkaline enzyme production was tested using 9 substrates.
Four different groups of Acremonium were separated based
on their enzyme production profiles. From these, isolate
WK276 (neutral rock-hole, south of Thailand) was selected
for further study. Of the nine enzymes, the α-amylase
properties of isolate WK276 were characterised. The Nterminal
of WK276 α-amylase was studied for developing
a specific primer. This was used to determine the complete
sequence coding for the α-amylase.
1130 - A time course study of functional and structural
differences between two Glomus mosseae isolates
L.M. Knudsen 1* , S. Dickson 2 , I. Jakobsen 1 & S.E. Smith 2
1 Risoe National Laboratory, PO BOX 49, 4000 Roskilde,
Denmark. - 2 Dept. of Soil and Water, University of
Adelaide, PMB 1, Glen Osmond, SA 5064, Australia. - Email:
lisa.munkvold@risoe.dk
A time course study was conducted with symbioses
between Cucumis sativus and two Glomus mosseae isolates
BEG161 and BEG29 previously shown to differ in hyphal
growth pattern. Four consecutive harvests were employed
to investigate plant growth and P uptake through time as
well as the development of intra- and extraradical
mycelium of the two fungi. Intraradical fungal structures
were visualised by light microscopy and laser scanning
confocal microscopy of NBT- and acid fuchsin-stained
sections. Mycorrhizal cucumber plants grew better and
reached higher P contents than non-mycorrhizal plants
within 29 days. However, the magnitude of the mycorrhizal
growth response depended on the fungal isolate. The rate
of intraradical development differed between the two
isolates, but reached the same final level. The most rapid
colonisation occurred in the time intervals 14-23 days and
23-29 days for BEG161 and BEG29, respectively. The
structure of the intraradical mycelium was similar, but
arbuscular branching patterns generally seemed very
variable. Finally, the present data show that cross walls, as
reported by Dickson & Smith (2001), are also formed in
arbuscular trunk hyphae of G. mosseae colonising C.
sativus.
1131 - The pecularieties of laccases biosynthesis by cocultivated
white-rot fungi Cerrena maxima and Coriolus
hirsutus
O.V. Koroleva 1 , V.P. Gavrilova 2* , E.V. Stepanova 1 , I.
Yavmetdinov 1 & A. Antipov 1
1 A.N.Bach Institute of Biochemistry Russian Academy of
Sciences, Leninskii pr.33, Moscow, 117071, Russia. -
2 V.L.Komarov Institute of Botany Russian Academy of
Sciences, Prof. Popova 2, St. Petersburg, 198022, Russia. -
E-mail: Valeria@VG2438.spb.edu