Isolation of the monooxygenase complex from Rhipicephalus (Boophilus) microplus – clues to understanding acaricide resistance

Abstract

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Chemical composition and acaricidal activity of seed oils of the palms Mauritia flexuosa and Mauritiella armata in Rhipicephalus microplus (Ixodidae)

“…Molecular studies have detected polymorphisms (Robbertse et al, 2016;Wyk et al, 2016;Bandara & Karunaratne, 2017;Sungirai et al, 2018) and changes in detoxification enzymes, such as esterases (Gaur et al, 2017) and monooxygenases (Graham et al 2016).…”

High-resolution melt (HRM) analysis for detection of SNPs associated with pyrethroid resistance in the southern cattle fever tick, Rhipicephalus (Boophilus) microplus (Acari: Ixodidae)

“…Since the discovery of the mutation in domain III of the putative para -sodium channel gene (He et al, 1999), a number of publications documented the presence of nucleotide polymorphisms in pyrethroid resistant populations of R. microplus across different geographic areas (Guerrero et al, 2001; Morgan et al, 2009; Rosario-Cruz et al, 2009; Aguirre et al, 2010; Jonsson et al, 2010; Rodriguez-Vivas et al, 2012; Lovis et al, 2012; Nogueira Domingues et al, 2012; Kumar et al, 2013; Robbertse et al, 2016; Wyk et al, 2016; Bandara and Karunaratne, 2017; Sungirai et al, 2018). In addition to target site insensitivity, other mechanisms involved in pyrethroid resistance among R. microplus populations include detoxification enzymes such as esterases (Guerrero et al, 2002; Singh and Rath, 2014; Gupta et al, 2016; Gaur et al, 2017), and monooxygenases (Graham et al, 2016).…”

Molecular quantitative assay for esterase-mediated organophosphate resistance in Rhipicephalus microplus

“…The use of chemical pesticides to control R. microplus ticks still is the most efficient method. However, the indiscriminate and inadequate use of some of them, such as organophosphates (OP), has induced development of resistance in cattle tick populations around the world (Miller et al, 2005;Baffi et al, 2008;Jyoti et al, 2014;Bendele et al, 2015;Graham et al, 2016;Jyoti et al, 2016;Robbertse et al, 2016). Despite this growing problem of resistance, the use of synthetic pyrethroids (SP) and OP pesticides for control of cattle tick populations in Brazil is very common (Mendes et al, 2011;Brito et al, 2011;Higa et al, 2015).…”

“…The inhibition of these enzymes causes over-stimulation of nicotinic and muscarinic acetylcholine receptors (Abdollahi et al, 2004). The complex mechanisms by which R. microplus develops resistance to OPs seems to involve dominant resistant alleles, gene copy number, transcript expression level, and splice variants in genes encoding specific enzyme families involved in the metabolism of this chemical group (Baxter and Barker, 1998;Hernandez et al, 1999;Baxter and Barker, 2002;Temeyer et al, 2004Temeyer et al, , 2007Bendele et al, 2015;Graham et al, 2016;Jyoti et al, 2016;Robbertse et al, 2016). Baxter and Baker (1998) found evidence that the establishment and maintenance of resistance occurs through a complex multifactorial process involving the esterase family of enzymes, especially AChEs.…”