The Role of Factor XIa (FXIa) Catalytic Domain Exosite Residues in Substrate Catalysis and Inhibition by the Kunitz Protease Inhibitor Domain of Protease Nexin 2

Su, Ya-Chi; Miller, Tara N.; Navaneetham, Duraiswamy; Schoonmaker, Robert T.; Sinha, Dipali; Walsh, Peter N.

doi:10.1074/jbc.m111.257527

Cited by 6 publications

(5 citation statements)

References 54 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…33 In addition, Lys554 is suggested to be part of the exosite for factor IX on the catalytic domain. 34 Unfortunately, except for the region in the catalytic domain, these proposed binding sites do not contain lysine residues or we were not able to detect these lysine residues. We have detected Lys554, but since it is located in a peptide containing Lys550 as well, it is difficult to determine the contribution of each of the two lysine residues to the TMT-127/TMT-126 ratio.…”

Section: Discussionmentioning

confidence: 86%

Chemical Footprinting Reveals Conformational Changes Following Activation of Factor XI

et al. 2018

View full text Add to dashboard Cite

Coagulation factor XI is activated by thrombin or factor XIIa resulting in a conformational change that converts the catalytic domain into its active form and exposing exosites for factor IX on the apple domains. Although crystal structures of the zymogen factor XI and the catalytic domain of the protease are available, the structure of the apple domains and hence the interactions with the catalytic domain in factor XIa are unknown. We now used chemical footprinting to identify lysine residue containing regions that undergo a conformational change following activation of factor XI. To this end, we employed tandem mass tag in conjunction with mass spectrometry. Fifty-two unique peptides were identified, covering 37 of the 41 lysine residues present in factor XI. Two identified lysine residues that showed altered flexibility upon activation were mutated to study their contribution in factor XI stability or enzymatic activity. Lys357, part of the connecting loop between A4 and the catalytic domain, was more reactive in factor XIa but mutation of this lysine residue did not impact on factor XIa activity. Lys516 and its possible interactor Glu380 are located in the catalytic domain and are covered by the activation loop of factor XIa. Mutating Glu380 enhanced Arg369 cleavage and thrombin generation in plasma. In conclusion, we have identified novel regions that undergo a conformational change following activation. This information improves knowledge about factor XI and will contribute to development of novel inhibitors or activators for this coagulation protein.

show abstract

Section: Discussionmentioning

confidence: 86%

Chemical Footprinting Reveals Conformational Changes Following Activation of Factor XI

et al. 2018

View full text Add to dashboard Cite

show abstract

“…It should be noted that in addition to accessibilities of cleavage sites, the amino acid sequences adjacent to the dibasic residue cleavage sites are also important for determining the preferences of proteases for cleavage sites 29–32. Therefore, while the cleavage sites #1, 4, 5, 11, and 12 show similar H‐D exchange compared with the most readily cleaved sites #6 and #7, the different amino acid sequences at such sites may participate in the lower extent of their proteolytic processing 15, 16, 27…”

Section: Discussionmentioning

confidence: 99%

Oxidizing Electrode Potentials Decrease Current Production and Coulombic Efficiency through Cytochrome c Inactivation in Shewanella oneidensis MR‐1

TerAvest

Angenent

2014

ChemElectroChem

View full text Add to dashboard Cite

Previous transcriptomic profiling of Shewanella oneidensis MR‐1 had suggested that electron transfer to an anode in a bioelectrochemical system may induce a general stress response (similar to a heat‐shock response) and/or an increase in protein turnover rates. Analysis of this microbe grown with a wide variety of electron acceptors also indicated that protein turnover may be related to the redox potential of the terminal electron acceptor. To investigate whether electrodes can induce stress and increase protein turnover, S. oneidensis was grown at potentiostatically poised electrodes at five redox potentials versus the standard hydrogen electrode (SHE) between −3 and +797 mVSHE. Subsequently, current production, coulombic efficiency, and transcription levels of marker genes for general stress and protein turnover were measured. Maximal current production was found at +397 mVSHE, and maximal coulombic efficiency was observed at +197 mVSHE. Both values decreased at more positive (oxidizing) potentials, that is, extracellular electron transfer of S. oneidensis is optimal at moderate electrode potentials. In contrast to previous findings, transcript measurements of a stress‐marker gene indicate that extracellular electron transfer does not increase general stress in comparison with aerobic respiration. Although overall protein turnover is not related to electrode potential, increased expression of a protease suggests that protein degradation increases at oxidizing electrode potentials. Cyclic voltammetry revealed decreased activity of c‐type cytochromes at the higher potentials, which indicates that oxidizing electrodes directly damage electron‐transfer proteins at the electrode surface.

show abstract

“…PN2KPI is a Kunitz protease inhibitor domain of the protease nexin 2 and can target the catalytic domain of FXIa. 34 Mutations in 2 PN2KPI loops, TGPCRAMISR and FYGGC, were detected, and the P1 site R15A was found to be essential for its ability to inhibit FXIa. 19 Subsequently, a Kunitz protease inhibitor, WPK5, which was identified from the leech Whitmania pigra , was mutated by replacing TGPCRAMISR and FYGGC in PN2KPI in our laboratory, and WPK5-Mut showed 100-fold greater potency than WPK5 against FXIa.…”

Section: Discussionmentioning

confidence: 99%

Dual Inhibition of Factor XIIa and Factor XIa Produces a Synergistic Anticoagulant Effect

Jiang,

Li,

Zhang

et al. 2024

Journal of Cardiovascular Pharmacology

View full text Add to dashboard Cite

Clinical practice shows that a critical unmet need in the field of thrombosis prevention is the availability of anticoagulant therapy without bleeding risk. Inhibitors against FXIa or FXIIa have been extensively studied because of their low bleeding risk. However, whether these compounds produce synergistic effects has not yet been explored. Here, analyses of activated partial thromboplastin time (aPTT) in combination with the FXIa inhibitor PN2KPI and the FXIIa inhibitor Infestin4 at different proportions were performed using the SynergyFinder tool identify synergistic anticoagulation effects. Both an FeCl3-induced carotid artery thrombosis mouse model and a transient occlusion of the middle cerebral artery (tMCAO) mouse model showed that the combination of PN2KPI and Infestin4, which are 28.57% and 6.25% of the effective dose, respectively, significantly prevents coagulation, and furthermore, dual inhibition does not cause bleeding risk.

show abstract

The Role of Factor XIa (FXIa) Catalytic Domain Exosite Residues in Substrate Catalysis and Inhibition by the Kunitz Protease Inhibitor Domain of Protease Nexin 2

Abstract: To select residues in coagulation factor

Cited by 6 publications

References 54 publications

Chemical Footprinting Reveals Conformational Changes Following Activation of Factor XI

Chemical Footprinting Reveals Conformational Changes Following Activation of Factor XI

Oxidizing Electrode Potentials Decrease Current Production and Coulombic Efficiency through Cytochrome c Inactivation in Shewanella oneidensis MR‐1

Dual Inhibition of Factor XIIa and Factor XIa Produces a Synergistic Anticoagulant Effect

Contact Info

Product

Resources

About