scholarly journals Overexpression of Cytochrome P450 CYP6B7 Mediated Pyrethroid Resistance in Indian Strains of the Cotton Bollworm, Helicoverpa Armigera (Hübner)

2014 ◽  
Vol 54 (3) ◽  
pp. 287-293 ◽  
Author(s):  
Ashraf Oukasha Abd El-Latif ◽  
Keshav Raj Kranthi ◽  
Sandhya Kranthi ◽  
Ali Sarwar ◽  
Bhattiprolu Subrahmanyam
Keyword(s):  
Cytochrome P450 ◽  
Helicoverpa Armigera ◽  
Pyrethroid Resistance ◽  
Cytochrome P450 Monooxygenase ◽  
Susceptible Strain ◽  
Cotton Bollworm ◽  
Strong Positive Correlation ◽  
P450 Monooxygenase ◽  
Monooxygenase Activity ◽  
Helicoverpa Armígera

Abstract The role of cytochrome P450 monooxygenase in pyrethroid resistance was studied in different strains of the cotton bollworm, Helicoverpa armigera, from India. Filed collected strains of Nagpur and Delhi were compared to the laboratory reared population. The results showed a high resistance to deltamethrin, α-cypermethrin, and β-cyfluthrin. The results also showed that this resistance could be reduced by using piperonyl butoxide (PBO). The Nagpur and Delhi strains were found to have a 2.40 and 1.79 fold higher monooxygenase activity compared to a susceptible strain. A strong, positive correlation between monooxygenase activity and pyrethroid resistance was observed (r = 0.86 - 0.98). The relative expression of the housekeeping gene, EF-1α, and three P450 genes, was studied in the 5th instar larval midgut of the three strains. Out of the three P450 genes examined, expression of CYP6B7 mRNA was not detected in the midgut of the susceptible strain though it was highly expressed in the resistant strains. The midgut of the Nagpur strain had a 2.60 fold overexpression of CYP6B7 mRNA compared to the moderately resistant, Delhi strain. The mRNA of CYP4G8 and CYP6B2 were not overexpressed in either the Nagpur or Delhi strain. The results indicated that the elevated cytochrome P450 monooxygenase activity is associated with pyrethroid resistance in Indian strains of H. armigera, and CYP6B7 could be the P450 form responsible for pyrethroid resistance.

Cytochrome P450 Monooxygenase Activity in the Dark Southern Subterranean Termite (Isoptera: Rhinotermitidae)

1998 ◽  
Vol 91 (5) ◽  
pp. 1131-1135 ◽  
Author(s):  
Steven M. Valles ◽  
Weste L. A. Osbrink ◽  
Faith M. Oi ◽  
Richard J. Brenner ◽  
Janine E. Powell
Keyword(s):  
Cytochrome P450 ◽  
Cytochrome P450 Monooxygenase ◽  
Subterranean Termite ◽  
P450 Monooxygenase ◽  
Monooxygenase Activity

scholarly journals Purification of Cytochrome P450 and Ferredoxin, Involved in Bisphenol A Degradation, from Sphingomonas sp. Strain AO1

2005 ◽  
Vol 71 (12) ◽  
pp. 8024-8030 ◽  
Author(s):  
Miho Sasaki ◽  
Ayako Akahira ◽  
Ko-ichi Oshiman ◽  
Tetsuaki Tsuchido ◽  
Yoshinobu Matsumura
Keyword(s):  
Mass Spectrometry ◽  
Cytochrome P450 ◽  
Bisphenol A ◽  
Cytochrome P450 Monooxygenase ◽  
Mass Spectrometry Analysis ◽  
Monooxygenase System ◽  
P450 Monooxygenase ◽  
Monooxygenase Activity ◽  
Chromatography Analysis ◽  
Ferredoxin Reductase

ABSTRACT In a previous study (M. Sasaki, J. Maki, K. Oshiman, Y. Matsumura, and T. Tsuchido, Biodegradation 16:449-459, 2005), the cytochrome P450 monooxygenase system was shown to be involved in bisphenol A (BPA) degradation by Sphingomonas sp. strain AO1. In the present investigation, we purified the components of this monooxygenase, cytochrome P450 (P450bisd), ferredoxin (Fdbisd), and ferredoxin reductase (Redbisd). We demonstrated that P450bisd and Fdbisd are homodimeric proteins with molecular masses of 102.3 and 19.1 kDa, respectively, by gel filtration chromatography analysis. Spectroscopic analysis of Fdbisd revealed the presence of a putidaredoxin-type [2Fe-2S] cluster. P450bisd, in the presence of Fdbisd, Redbisd, and NADH, was able to convert BPA. The Km and k cat values for BPA degradation were 85 ± 4.7 μM and 3.9 ± 0.04 min−1, respectively. NADPH, spinach ferredoxin, and spinach ferredoxin reductase resulted in weak monooxygenase activity. These results indicated that the electron transport system of P450bisd might exhibit strict specificity. Two BPA degradation products of the P450bisd system were detected by high-performance liquid chromatography analysis and were thought to be 1,2-bis(4-hydroxyphenyl)-2-propanol and 2,2-bis(4-hydroxyphenyl)-1-propanol based on mass spectrometry-mass spectrometry analysis. This is the first report demonstrating that the cytochrome P450 monooxygenase system in bacteria is involved in BPA degradation.

scholarly journals Resistance of Australian Helicoverpa armigera to fenvalerate is due to the chimeric P450 enzyme CYP337B3

2012 ◽  
Vol 109 (38) ◽  
pp. 15206-15211 ◽  
Author(s):  
Nicole Joußen ◽  
Sara Agnolet ◽  
Sybille Lorenz ◽  
Sebastian E. Schöne ◽  
Renate Ellinger ◽  
...  
Keyword(s):  
Helicoverpa Armigera ◽  
Pyrethroid Resistance ◽  
Resistance Mechanism ◽  
Metabolic Resistance ◽  
P450 Monooxygenase ◽  
Pyrethroid Insecticides ◽  
Wide Range ◽  
P450 Enzyme ◽  
Helicoverpa Armígera ◽  
Genetic Mechanisms

Worldwide, increasing numbers of insects have evolved resistance to a wide range of pesticides, which hampers their control in the field and, therefore, threatens agriculture. Members of the carboxylesterase and cytochrome P450 monooxygenase superfamilies are prominent candidates to confer metabolic resistance to pyrethroid insecticides. Both carboxylesterases and P450 enzymes have been shown to be involved in pyrethroid resistance in Australian Helicoverpa armigera, the noctuid species possessing by far the most reported resistance cases worldwide. However, specific enzymes responsible for pyrethroid resistance in field populations of this species have not yet been identified. Here, we show that the resistance toward fenvalerate in an Australian strain of H. armigera is due to a unique P450 enzyme, CYP337B3, which arose from unequal crossing-over between two parental P450 genes, resulting in a chimeric enzyme. CYP337B3 is capable of metabolizing fenvalerate into 4′-hydroxyfenvalerate, which exhibits no toxic effect on susceptible larvae; enzymes from the parental P450 genes showed no detectable fenvalerate metabolism. Furthermore, a polymorphic H. armigera strain could be bred into a susceptible line possessing the parental genes CYP337B1 and CYP337B2 and a resistant line possessing only CYP337B3. The exclusive presence of CYP337B3 in resistant insects of this strain confers a 42-fold resistance to fenvalerate. Thus, in addition to previously documented genetic mechanisms of resistance, recombination can also generate selectively advantageous variants, such as this chimeric P450 enzyme with an altered substrate specificity leading to a potent resistance mechanism.

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