Table 1.

Cytochrome P450 activity of various enzyme preparations from the Marin colony measured using Lu-H or 7-EC as substrates

Type of preparation	Abbreviation	Enzyme source	n per preparation	Assay time (min)a	Protein (µg) per mosquito (mean ± SD)	Activityb	Activity per assay timec
Microsome	Mgut	Cleared gutd	100	290	1.92 (0.578)	209	0.72
Homogenate (Lu-H)	Hwhole	Whole larva	30	55	79.4 (11.7)	–e	–
	Hheadless	Headless larva	30	70	63.2 (11.5)	–	–
	Hcarcass	Carcassf	30	70	33.2 (1.20)	–	–
	Hhead	Head	30	70	15.1 (1.28)	–	–
	Hgut	Cleared gut	30	108	28.7 (3.43)	68.9	0.64
	Hcaecae	Caecae	30	108	10.3 (1.03)	16.8	0.16
	Hventriculus	Ventriculus	30	108	11.8 (0.883)	71.8	0.66
	Htubules	Malpighian tubules	30	108	6.70 (1.01)	25.2	0.23
	S-Hgut	Cleared gut	27	100	31.2 (2.12)	33.5g	0.34
Whole tissue	Sgut(Lu-H)	Cleared gut	40	85	36.1 (5.73)h	112g	1.3
Whole tissue	Sgut(7-EC)	Cleared gut	22	280	36.1 (5.73)h	1,840g	6.6
Whole larva	Slive(Lu-H)	Live larva	40	55	89.2 (2.38)h	0.964g	0.0175
Whole larva	Slive(7-EC)	Live larva	119	250	89.2 (2.38)h	117g	0.47
Whole larva (Lu-H)	Sdead	Dead larva	6	250	89.2 (2.38)h	–	–
Blank	Bwater	Larval panwater	NA	55	NA	–	–

The 7-EC substrate was used for two preparations (whole tissue and whole larvae).

^aDoes not include buffer and reagent preparation or luminescent signal stabilization time.

^bPmoles substrate (luciferin or 7-OH coumarin) per minute per microgram protein.

^cActivity per assay time was calculated by dividing activity reading by assay time.

^dCleared gut: midgut (gastric cecae + ventriculus) and malpighian tubules cleared of food content.

^eActivity not detectable with Lu-H at high protein concentration or with single dead larvae.

^fCarcass: headless and gutless body.

^gIndividual mosquitoes assayed, average activity per individual larvae is reported.

^hProtein measurements from single cleared gut/whole larvae homogenates without centrifugation.

–, no activity detected; NA, not applicable.