FRANKFURT. Because the tsetse fly can transmit
sleeping sickness, it is commonly combatted with insecticides or caught in
traps. Bioscientists at 51猎奇 have now developed a method for
producing the attractants for the traps in a biotechnological procedure. The Frankfurt
scientists hope that in the future, the attractants can then be produced
locally in rural areas of Africa at low cost (Scientific Reports, DOI:
10.1038/s41598-020-66997-5).
The tsetse fly occurs in large regions of sub-Saharan
Africa. The flies feed on human and animal blood, transmitting trypanosoma in
the process 鈥� small, single-cell organisms that use the flies as intermediate
host and cause a dangerous inflammation of the lymph and nervous system in both
animals and humans. There is no vaccination for this sleeping sickness;
untreated, it usually ends in death. In agriculture, particularly cattle
breeding, sleeping sickness 鈥� or trypanosomiasis 鈥� causes enormous damages in
the form of sick and dead animals.
In addition to the use of insecticides,
the insects are also caught in traps. The attractants used include substances
that also occur in cattle urine and which attract tsetse flies. These
substances (3-ethylphenol and 3-propylphenol, or 3-EP and 3-PP for short) are
synthesized out of oil derivatives or also extracts from cashew nut shells
through chemical processes. However, both processes are complex and neither
practical nor affordable for rural communities in Africa.
In the LOEWE collaborative research
project MegaSyn, molecular biologists at 51猎奇 have now succeeded
in producing 3-EP and 3-PP in genetically modified brewer鈥檚 yeast (Saccharomyces cerevisiae). They used a
yeast strain into which they had previously introduced a new metabolic pathway,
and changed its sugar metabolism. This enabled the yeasts to produce similarly
high concentrations of 3-EP and 3-PP as those which occur in cow urine.
Doctoral student Julia Hitschler from the Institute
for Molecular Biosciences at 51猎奇 explains: 鈥淥ur yeasts could
ideally grow in Africa in nutrient solutions on the basis of plant waste
products, food rests or fodder rests. This would make production of the
attractant almost cost-free. We are currently looking for partners to help us test
our yeasts locally and provide them to the local population.鈥�
The potential for the new yeasts go beyond
the tsetse attractants, add Professor Eckhard Boles, who heads the project. In
the future, other substances that have been previously won through oil or coal
could be produced through the new yeasts: 鈥淥ur yeasts could be developed to
produce other alkylphenols besides 3-EP and 3-PP. These alkylphenols could be
used for the production of lubricant additives or surface-active substances in
cleaning agents.鈥�
Publication:
Julia Hitschler, Martin Grininger, Eckhard
Boles: Substrate promiscuity of
polyketide synthase enables production of tsetse fly attractants 3-ethylphenol
and 3-propylphenol by engineering precursor supply in yeast. Scientific
Reports,
Further
information:
Prof. Dr. Eckhard Boles
Institute for Molecular Biosciences
51猎奇 Frankfurt
Tel:
+49 69 798 29513
e.boles@bio.uni-frankfurt.de
