Banca de QUALIFICAÇÃO: EDUARDO JOSE AZEVEDO CORREA

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : EDUARDO JOSE AZEVEDO CORREA
DATE: 30/06/2022
TIME: 09:00
LOCAL: meet.google.com/ikw-yazg-eup
TITLE:

Experimental and computational studies of essential oils insecticidal action on Calliphoridae flies and identification of their possible molecular targets

KEY WORDS:

Computational biology, virtual screening, essential oils, Baccharis dracunculifolia, blowfly

PAGES: 59
BIG AREA: Ciências Biológicas
AREA: Bioquímica
SUBÁREA: Química de Macromoléculas
SPECIALTY: Proteínas
SUMMARY:

The biological and technological properties of essential oils have been object of scientific research for decades.
However, the intricacies of their mechanism of action remains ellusive. In chemoinformatics the structural features
of molecules are described by Physico-chemical properties derived from the molecular structure like polarizability,
molecular volume and weight, hidrophobicity and other. Thus, identify a relevant molecular signature of
compounds that could be used to inteffer on biological mechanism of insects could lead to production of more
safe, effective, and selective insecticide agents. Based on the computational methodology, this work aimed to
predict the composition/structure/function relationship of essential oils compounds and their molecular targets
over the non-biting blowflies of the Calliphoridae family and the experimental validation of a predicted oil as
significantly promising. In this regard, a virtual database with 651 biologically active plant essential oils
compounds are performed, chosen after being assembled based on previous literature reviews and from digital
natural essential oils compounds from databases Systematic X. Virtual screening assays stem from this database
were performed on archetypal molecular targets to commercial insecticides and documented sensitive essential oil
components. Targets were selected based on neurochemical (acetylcholinesterase (AChE) and γ-aminobutyric acid
class a receptor (GABAaR)); neurohormonal and neuromodulators (octopamine receptor (OctpR)); proteins
responsible for the growth and metamorphosis (ecdysone nuclear receptor (EcNR) and methoprene tolerant
protein, a juvenile hormone insect receptor (MET)) and hormone carriage (juvenile odorant family hormone
binding protein (JHBP)), For EcNR, UsNR, and OctpR, and their possible agonist and antagonist binding
conformations were also considered. The highest hits, top 1 to 2 % affinity of compounds, for each target were
obtained by a rigorous methodology of clustering scores by ranking functions best suited for each system. By
analyzing chemoinformatics descriptors of the hits molecules, we can determine the pharmacophore signatures to
such assertive groups were then estimated considering both ligands themselves and their target association to it.
The essential oil components profiled for three plant species and with described insecticidal action were compared
to these signatures, and the Baccharis dracunculifolia essential oil was selected for experimental validation.
Bioassays with fresh essential oil extracted of B. dracunculifolia oil on Chrysomya sp larvae and adults proved
substantial pharmacophoric consonance of its oil components to different biocide targets (showing an LD50 of
20.94%) and particularly its high MET receptor association signature (given the marked anti-metamorphic
symptoms observed). Taking this data together, the present study points out the success of a promising
methodology that could identify insecticidal pharmacophore signatures on plants' essential oils, which could be of
high value for the bioprospection of new natural extracts and molecules of agro-health interest.

BANKING MEMBERS:
Presidente - 2981680 - LEONARDO HENRIQUE FRANCA DE LIMA
Externo ao Programa - 1727278 - LUIZ GUSTAVO DE LIMA GUIMARAES
Externo à Instituição - RAFAELA SALGADO FERREIRA - UFMG