TITLE:
Affiliation of Dihydrolipoyl Dehydrogenase Allozymes in Mycorrhizae of European Forest Trees and Characterization of the Enzyme of the Matt Bolete (Xerocomus pruinatus) and the Bay Bolete (X. badius)
AUTHORS:
Uwe Schirkonyer, Gunter M. Rothe
KEYWORDS:
Amino Acid Sequence, cDNA, Ectomycorrhizae, Fagus sylvatica, Gene Sequence, Larix decidua, mRNA, Dihydrolipoyl Dehydrogenase, Picea abies, Quercus petraea, Xerocomus pruinatus, Xerocomus badius
JOURNAL NAME:
Open Journal of Ecology,
Vol.8 No.6,
June
15,
2018
ABSTRACT: Mycorrhizal roots of the deciduous trees European
beech (Fagus sylvatica (L.)) and
Sessile oak (Quercus petraea (MattuschkaLiebl.)) and the conifers Norway spruce (Picea abies (L.) H. Karst.) and European larch (Larix decidua (Mill.)) associated with
the ectomycorrhizal fungi matt bolete (Xerocomus
pruinatus (Fries 1835)) or bay bolete (X.
badius (Fries 1818)) were analysed with respect to the occurrence of
dihydrolipoyl dehydrogenase (EC 1.8.1.4) allozymes. In root tissues of the two
deciduous trees, two gene loci could be
visualized after cellulose acetate electrophoresis while three loci were expressed
in root tissues of the two coniferous species. The two fungal species and
further ectomycorrhizal fungi expressed exclusively one dihydrolipoyl
dehydrogenase gene. In Xerocomus
pruinatus and X. badius, the dihydrolipoyl dehydrogenase gene consists of 1460 bp and 1370 bp,
respectively, including five introns each consisting of 52 bp. Their DNA
sequences correspond to 70 to 90% to other fungal dihydrolipoyl dehydrogenase
genes. One monomer of the dimeric dihydrolipoyl dehydrogenase enzyme consists
of 486 (X. pruinatus) or 454 (X. badius) amino acids which sum up to a
molecular mass of 55 kDa (X. pruinatus),
respectively 52 kDa (X. badius). The
number of positively charged amino acid residues makes 79 (X. pruinatus) and 68 (X.
badius) and the number of negatively charged amino acid residues was
calculated to make 46 (X. pruinatus)
and 48 (X. badius); isoelectric
points make 9.99 (X. pruinatus) and
9.68 (X. badius). Calculated three
dimensional structures reveal a short NADH binding site being part of a larger
FAD-binding site and a binding/dimerization domain.