title: N-terminal domain of Bothrops asper Myotoxin II Enhances the Activity of Endothelin Converting Enzyme-1 and Neprilysin.
abstract: Neprilysin (NEP) and endothelin converting enzyme-1 (ECE-1) are two enzymes that degrade amyloid beta in the brain. Currently there are no molecules to stimulate the activity of these enzymes. Here we report, the discovery and characterisation of a peptide referred to as K49-P1-20, from the venom of Bothrops asper which directly enhances the activity of both ECE-1 and NEP. This is evidenced by a 2- and 5-fold increase in the Vmax of ECE-1 and NEP respectively. The K49-P1-20 concentration required to achieve 50% of maximal stimulation (AC50) of ECE-1 and NEP was 1.92 ± 0.07 and 1.33 ± 0.12 μM respectively. Using BLITZ biolayer interferometry we have shown that K49-P1-20 interacts directly with each enzyme. Intrinsic fluorescence of the enzymes change in the presence of K49-P1-20 suggesting a change in conformation. ECE-1 mediated reduction in the level of endogenous soluble amyloid beta 42 in cerebrospinal fluid is significantly higher in the presence of K49-P1-20 (31 ± 4% of initial) compared with enzyme alone (11 ± 5% of initial; N = 8, P = 0.005, unpaired t-test). K49-P1-20 could be an excellent research tool to study mechanism(s) of enzyme stimulation, and a potential novel drug lead in the fight against Alzheimer's disease.
authors.affiliation: Department of Biochemistry &Molecular Biology, Biomedical Discovery Institute, Monash University, Clayton, Vic 3800, Australia.
authors.forename: A Ian
authors.initials: AI
authors.lastname: Smith
authors.affiliation: Baker IDI Heart and Diabetes Institute, 75 Commercial Road, Melbourne, Victoria 3004, Australia.|Department of Physiology, Biomedical Discovery Institute, Monash University, Clayton, Vic 3800, Australia.
authors.forename: Niwanthi W
authors.initials: NW
authors.lastname: Rajapakse
authors.affiliation: Department of Biochemistry &Molecular Biology, Biomedical Discovery Institute, Monash University, Clayton, Vic 3800, Australia.
authors.forename: Oded
authors.initials: O
authors.lastname: Kleifeld
authors.affiliation: Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José, Costa Rica.
authors.forename: Bruno
authors.initials: B
authors.lastname: Lomonte
authors.affiliation: Department of Pharmacology, Biomedical Discovery Institute, Monash University, Clayton, Vic 3800, Australia.
authors.forename: Nkumbu L
authors.initials: NL
authors.lastname: Sikanyika
authors.affiliation: Department of Pharmacology, Biomedical Discovery Institute, Monash University, Clayton, Vic 3800, Australia.
authors.forename: Alexander J
authors.initials: AJ
authors.lastname: Spicer
authors.affiliation: Department of Pharmacology, Biomedical Discovery Institute, Monash University, Clayton, Vic 3800, Australia.
authors.forename: Wayne C
authors.initials: WC
authors.lastname: Hodgson
authors.affiliation: Department of Biochemistry &Molecular Biology, Biomedical Discovery Institute, Monash University, Clayton, Vic 3800, Australia.
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Conroy
authors.affiliation: Menzies Research Institute, University of Tasmania, Hobart, Tasmania 7000, Australia.
authors.forename: David H
authors.initials: DH
authors.lastname: Small
authors.affiliation: Baker IDI Heart and Diabetes Institute, 75 Commercial Road, Melbourne, Victoria 3004, Australia.
authors.forename: David M
authors.initials: DM
authors.lastname: Kaye
authors.affiliation: Department of Physiology, Biomedical Discovery Institute, Monash University, Clayton, Vic 3800, Australia.
authors.forename: Helena C
authors.initials: HC
authors.lastname: Parkington
authors.affiliation: Department of Biochemistry &Molecular Biology, Biomedical Discovery Institute, Monash University, Clayton, Vic 3800, Australia.
authors.forename: James C
authors.initials: JC
authors.lastname: Whisstock
authors.affiliation: Department of Biochemistry &Molecular Biology, Biomedical Discovery Institute, Monash University, Clayton, Vic 3800, Australia.
authors.forename: Sanjaya
authors.initials: S
authors.lastname: Kuruppu
mesh_terms: D000409:Alanine / Q000378:metabolism; D000595:Amino Acid Sequence; D000072396:Endothelin-Converting Enzymes / Q000378:metabolism*; D004789:Enzyme Activation / Q000187:drug effects; D057075:Enzyme Assays; D054501:Group II Phospholipases A2 / Q000737:chemistry* / Q000494:pharmacology*; D057809:HEK293 Cells; D006801:Humans; D007700:Kinetics; D015260:Neprilysin / Q000378:metabolism*; D010455:Peptides / Q000737:chemistry / Q000378:metabolism; D000072417:Protein Domains; D030162:Reptilian Proteins / Q000737:chemistry* / Q000494:pharmacology*; D013329:Structure-Activity Relationship
chemical_list: D010455:Peptides; D030162:Reptilian Proteins; D054501:Group II Phospholipases A2; C061056:myotoxin II, Bothrops asper; D015260:Neprilysin; D000072396:Endothelin-Converting Enzymes; D000409:Alanine