Metal Ions as Cofactors for the Binding of Inhibitors to Methionine Aminopeptidase: A Critical View of the Relevance of In Vitro Metalloenzyme Assays

Schiffmann, Rolf; Heine, A.; Klebe, G.; Klein, Christian D.

doi:10.1002/anie.200500592

Cited by 59 publications

(59 citation statements)

References 20 publications

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“…Metal ions such as Mg, Mn, Zn, Cu, Ca, Na and Fe are essential for cell mass formation and also they act as cofactors for several bio-synthetic enzymes (Schiffmann et al, 2005). In the present study it was found that 0.1 % of manganese enhanced the L-asparaginase production followed by copper sulphate and zinc sulphate (4.11 IU) and least activity by magnesium sulphate (3.83 IU) ( Figure-13).…”

Section: Metal Ionssupporting

confidence: 49%

Production of l-asparaginase from rhizosphere soil fungus aspergillus tamari

S¹,

B²

2017

Int j curr adv res

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Section: Metal Ionssupporting

confidence: 49%

Production of l-asparaginase from rhizosphere soil fungus aspergillus tamari

S¹,

B²

2017

Int j curr adv res

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“…Purified MetAP apoenzyme can be reproducibly activated by a number of divalent metal ions, such as Co(II), Mn(II), Ni(II), and Fe(II) (11,12). Among them, Co(II) is one of the best activators of the enzyme, and many MetAP inhibitors were discovered by screening on purified MetAP with high Co(II) concentrations in the activity assay (13). Several x-ray structures of MetAP with or without an inhibitor bound showed that the catalytic site is a shallow pocket with two Co(II) ions situated at the bottom for a dinuclear arrangement (14).…”

mentioning

confidence: 99%

“…Potent MetAP inhibitors have been identified, but none of the inhibitors have shown significant antibacterial activity (13,22,23). Although most of the current MetAP inhibitors inhibit the Co(II)-form of MetAP effectively, their potency on other metalloforms often has not been characterized.…”

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confidence: 99%

FE(II) Is the Native Cofactor for Escherichia coli Methionine Aminopeptidase

Chai

Wang

2008

Journal of Biological Chemistry

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“…Therefore, human MetAPs may also serve as targets for the development of new anticancer agents. Some small molecules that inhibit MetAPs potently in vitro are known, but they lack potent antibacterial (10)(11)(12) or antiangiogenic (13) activities. One reason for this failure may be that they do not penetrate the bacterial or mammalian cells to reach their intended target, or perhaps they are efficiently transported back out of the cells.…”

mentioning

confidence: 99%

“…These metal ions are suggested to bind and activate the water for deprotonation and assist the nucleophilic attack, whereas the metal ion M2 also binds the free unprotonated amino group of the methionine residue (P1) of the substrate for a productive bound conformation. In some recent structures, a third divalent metal ion is also present, serving as a bridge between a small molecule ligand and active-site groups on the enzyme (11,(22)(23)(24). Despite the great number of x-ray structures of these enzymes that show two or even three divalent metal ions bound in the active-site region, metal titration studies indicate that some of these metalloaminopeptidases can function fully with only a single metal ion bound.…”

mentioning

confidence: 99%

Structural basis of catalysis by monometalated methionine aminopeptidase

Xie

Qiang

et al. 2006

Proc. Natl. Acad. Sci. U.S.A.

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Methionine aminopeptidase (MetAP) removes the amino-terminal methionine residue from newly synthesized proteins, and it is a target for the development of antibacterial and anticancer agents. Available x-ray structures of MetAP, as well as other metalloaminopeptidases, show an active site containing two adjacent divalent metal ions bridged by a water molecule or hydroxide ion. The predominance of dimetalated structures leads naturally to proposed mechanisms of catalysis involving both metal ions. However, kinetic studies indicate that in many cases, only a single metal ion is required for full activity. By limiting the amount of metal ion present during crystal growth, we have now obtained a crystal structure for a complex of Escherichia coli MetAP with norleucine phosphonate, a transition-state analog, and only a single Mn(II) ion bound at the active site in the position designated M1, and three related structures of the same complex that show the transition from the mono-Mn(II) form to the di-Mn(II) form. An unliganded structure was also solved. In view of the full kinetic competence of the monometalated MetAP, the much weaker binding constant for occupancy of the M2 site compared with the M1 site, and the newly determined structures, we propose a revised mechanism of peptide bond hydrolysis by E. coli MetAP. We also suggest that the crystallization of dimetalated forms of metallohydrolases may, in some cases, be a misleading experimental artifact, and caution must be taken when structures are generated to aid in elucidation of reaction mechanisms or to support structure-aided drug design efforts.metalloprotease ͉ protein structure ͉ enzyme inhibition ͉ drug discovery ͉ metal occupancy A ll newly synthesized proteins have an amino-terminal methionine residue corresponding to the start codon AUG. In a significant number of cases, this initiating methionine residue is removed, either co-or posttranslationally, by the enzyme methionine aminopeptidase (MetAP) (1). In bacteria, this enzyme is the product of a single gene, and it is absolutely essential for bacterial survival, as demonstrated by gene deletion experiments in Escherichia coli (2) and Salmonella typhimurium (3). The single but critically essential MetAP enzyme of bacteria thus stands out as an attractive target for the design of antibacterial agents (4). Eukaryotes, on the other hand, have two distinct MetAPs, types I and II, arising from different genes (5). The human type II MetAP is a target of the antiangiogenic compounds fumagillin, ovalicin, and TNP-470 (6-8). Bengamides inhibit both types of MetAP (9) and cause inhibition of the growth of several human tumor cell lines in vitro at low-nanomolar concentrations. Therefore, human MetAPs may also serve as targets for the development of new anticancer agents. Some small molecules that inhibit MetAPs potently in vitro are known, but they lack potent antibacterial (10-12) or antiangiogenic (13) activities. One reason for this failure may be that they do not penetrate the bacterial or mammalian cells to...

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Metal Ions as Cofactors for the Binding of Inhibitors to Methionine Aminopeptidase: A Critical View of the Relevance of In Vitro Metalloenzyme Assays

Cited by 59 publications

References 20 publications

Production of l-asparaginase from rhizosphere soil fungus aspergillus tamari

Production of l-asparaginase from rhizosphere soil fungus aspergillus tamari

FE(II) Is the Native Cofactor for Escherichia coli Methionine Aminopeptidase

Structural basis of catalysis by monometalated methionine aminopeptidase

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