The M17 leucine aminopeptidase of the malaria parasite Plasmodium falciparum : importance of active site metal ions in the binding of substrates and inhibitors
(2009) In Biochemistry 48(23). p.9-5435- Abstract
The M17 leucine aminopeptidase of the intraerythrocytic stages of the malaria parasite Plasmodium falciparum (PfLAP) plays a role in releasing amino acids from host hemoglobin that are used for parasite protein synthesis, growth, and development. This enzyme represents a target at which new antimalarials could be designed since metalloaminopeptidase inhibitors prevent the growth of the parasites in vitro and in vivo. A study on the metal ion binding characteristics of recombinant P. falciparum M17 leucine aminopeptidase (rPfLAP) shows that the active site of this exopeptidase contains two metal-binding sites, a readily exchangeable site (site 1) and a tight binding site (site 2). The enzyme retains activity when the metal ion is removed... (More)
The M17 leucine aminopeptidase of the intraerythrocytic stages of the malaria parasite Plasmodium falciparum (PfLAP) plays a role in releasing amino acids from host hemoglobin that are used for parasite protein synthesis, growth, and development. This enzyme represents a target at which new antimalarials could be designed since metalloaminopeptidase inhibitors prevent the growth of the parasites in vitro and in vivo. A study on the metal ion binding characteristics of recombinant P. falciparum M17 leucine aminopeptidase (rPfLAP) shows that the active site of this exopeptidase contains two metal-binding sites, a readily exchangeable site (site 1) and a tight binding site (site 2). The enzyme retains activity when the metal ion is removed from site 1, while removal of metal ions from both sites results in an inactive apoenzyme that cannot be reactivated by the addition of divalent metal cations. The metal ion at site 1 is readily exchangeable with several divalent metal ions and displays a preference in the order of preference Zn(2+) > Mn(2+) > Co(2+) > Mg(2+). While it is likely that native PfLAP contains a Zn(2+) in site 2, the metal ion located in site 1 may be dependent on the type and concentration of metal ions in the cytosolic compartment of the parasite. Importantly, the type of metal ion present at site 1 influences not only the catalytic efficiency of the enzyme for peptide substrates but also the mode of binding by bestatin, a metal-chelating inhibitor of M17 aminopeptidases with antimalarial activity.
(Less)
- author
- Maric, Selma LU ; Donnelly, Sheila M ; Robinson, Mark W ; Skinner-Adams, Tina ; Trenholme, Katharine R ; Gardiner, Donald L ; Dalton, John P ; Stack, Colin M and Lowther, Jonathan
- publishing date
- 2009-06-16
- type
- Contribution to journal
- publication status
- published
- keywords
- Animals, Binding Sites, Catalytic Domain, Enzyme Inhibitors/chemistry, Kinetics, Leucyl Aminopeptidase/chemistry, Metals/chemistry, Plasmodium falciparum/enzymology, Recombinant Proteins/chemistry, Structure-Activity Relationship, Substrate Specificity
- in
- Biochemistry
- volume
- 48
- issue
- 23
- pages
- 5 pages
- publisher
- The American Chemical Society (ACS)
- external identifiers
-
- pmid:19408962
- scopus:67049154265
- ISSN
- 0006-2960
- DOI
- 10.1021/bi9003638
- language
- English
- LU publication?
- no
- id
- 5117d221-c71a-400c-a104-e1e8774eaff3
- date added to LUP
- 2018-07-19 11:56:40
- date last changed
- 2024-06-24 17:05:39
@article{5117d221-c71a-400c-a104-e1e8774eaff3, abstract = {{<p>The M17 leucine aminopeptidase of the intraerythrocytic stages of the malaria parasite Plasmodium falciparum (PfLAP) plays a role in releasing amino acids from host hemoglobin that are used for parasite protein synthesis, growth, and development. This enzyme represents a target at which new antimalarials could be designed since metalloaminopeptidase inhibitors prevent the growth of the parasites in vitro and in vivo. A study on the metal ion binding characteristics of recombinant P. falciparum M17 leucine aminopeptidase (rPfLAP) shows that the active site of this exopeptidase contains two metal-binding sites, a readily exchangeable site (site 1) and a tight binding site (site 2). The enzyme retains activity when the metal ion is removed from site 1, while removal of metal ions from both sites results in an inactive apoenzyme that cannot be reactivated by the addition of divalent metal cations. The metal ion at site 1 is readily exchangeable with several divalent metal ions and displays a preference in the order of preference Zn(2+) > Mn(2+) > Co(2+) > Mg(2+). While it is likely that native PfLAP contains a Zn(2+) in site 2, the metal ion located in site 1 may be dependent on the type and concentration of metal ions in the cytosolic compartment of the parasite. Importantly, the type of metal ion present at site 1 influences not only the catalytic efficiency of the enzyme for peptide substrates but also the mode of binding by bestatin, a metal-chelating inhibitor of M17 aminopeptidases with antimalarial activity.</p>}}, author = {{Maric, Selma and Donnelly, Sheila M and Robinson, Mark W and Skinner-Adams, Tina and Trenholme, Katharine R and Gardiner, Donald L and Dalton, John P and Stack, Colin M and Lowther, Jonathan}}, issn = {{0006-2960}}, keywords = {{Animals; Binding Sites; Catalytic Domain; Enzyme Inhibitors/chemistry; Kinetics; Leucyl Aminopeptidase/chemistry; Metals/chemistry; Plasmodium falciparum/enzymology; Recombinant Proteins/chemistry; Structure-Activity Relationship; Substrate Specificity}}, language = {{eng}}, month = {{06}}, number = {{23}}, pages = {{9--5435}}, publisher = {{The American Chemical Society (ACS)}}, series = {{Biochemistry}}, title = {{The M17 leucine aminopeptidase of the malaria parasite Plasmodium falciparum : importance of active site metal ions in the binding of substrates and inhibitors}}, url = {{http://dx.doi.org/10.1021/bi9003638}}, doi = {{10.1021/bi9003638}}, volume = {{48}}, year = {{2009}}, }