A Theory of Enzyme Chemotaxis: From Experiments to Modeling

Farzad Mohajerani, Xi Zhao, Ambika Somasundar, Darrell Velegol, Ayusman Sen

Research output: Contribution to journalArticle

16 Citations (Scopus)

Abstract

Enzymes show two distinct transport behaviors in the presence of their substrates in solution. First, their diffusivity enhances with an increasing substrate concentration. In addition, enzymes perform directional motion toward regions with a high substrate concentration, termed as chemotaxis. While a variety of enzymes has been shown to undergo chemotaxis, there remains a lack of quantitative understanding of the phenomenon. Here, we derive a general expression for the active movement of an enzyme in a concentration gradient of its substrate. The proposed model takes into account both the substrate-binding and catalytic turnover step, as well as the enhanced diffusion of the enzyme. We have experimentally measured the chemotaxis of a fast and a slow enzyme: urease under catalytic conditions and hexokinase for both full catalysis and for simple noncatalytic substrate binding. There is good agreement between the proposed model and the experiments. The model is general, has no adjustable parameters, and only requires three experimentally defined constants to quantify chemotaxis: enzyme-substrate binding affinity (Kd), Michaelis-Menten constant (KM), and level of diffusion enhancement in the associated substrate (α).

Original languageEnglish (US)
Pages (from-to)6256-6263
Number of pages8
JournalBiochemistry
Volume57
Issue number43
DOIs
StatePublished - Oct 30 2018

Fingerprint

Chemotaxis
Substrates
Enzymes
Experiments
Hexokinase
Urease
Catalysis

All Science Journal Classification (ASJC) codes

  • Biochemistry

Cite this

Mohajerani, Farzad ; Zhao, Xi ; Somasundar, Ambika ; Velegol, Darrell ; Sen, Ayusman. / A Theory of Enzyme Chemotaxis : From Experiments to Modeling. In: Biochemistry. 2018 ; Vol. 57, No. 43. pp. 6256-6263.
@article{662d6abcc6034f87b697fefd7f81e53b,
title = "A Theory of Enzyme Chemotaxis: From Experiments to Modeling",
abstract = "Enzymes show two distinct transport behaviors in the presence of their substrates in solution. First, their diffusivity enhances with an increasing substrate concentration. In addition, enzymes perform directional motion toward regions with a high substrate concentration, termed as chemotaxis. While a variety of enzymes has been shown to undergo chemotaxis, there remains a lack of quantitative understanding of the phenomenon. Here, we derive a general expression for the active movement of an enzyme in a concentration gradient of its substrate. The proposed model takes into account both the substrate-binding and catalytic turnover step, as well as the enhanced diffusion of the enzyme. We have experimentally measured the chemotaxis of a fast and a slow enzyme: urease under catalytic conditions and hexokinase for both full catalysis and for simple noncatalytic substrate binding. There is good agreement between the proposed model and the experiments. The model is general, has no adjustable parameters, and only requires three experimentally defined constants to quantify chemotaxis: enzyme-substrate binding affinity (Kd), Michaelis-Menten constant (KM), and level of diffusion enhancement in the associated substrate (α).",
author = "Farzad Mohajerani and Xi Zhao and Ambika Somasundar and Darrell Velegol and Ayusman Sen",
year = "2018",
month = "10",
day = "30",
doi = "10.1021/acs.biochem.8b00801",
language = "English (US)",
volume = "57",
pages = "6256--6263",
journal = "Biochemistry",
issn = "0006-2960",
publisher = "American Chemical Society",
number = "43",

}

A Theory of Enzyme Chemotaxis : From Experiments to Modeling. / Mohajerani, Farzad; Zhao, Xi; Somasundar, Ambika; Velegol, Darrell; Sen, Ayusman.

In: Biochemistry, Vol. 57, No. 43, 30.10.2018, p. 6256-6263.

Research output: Contribution to journalArticle

TY - JOUR

T1 - A Theory of Enzyme Chemotaxis

T2 - From Experiments to Modeling

AU - Mohajerani, Farzad

AU - Zhao, Xi

AU - Somasundar, Ambika

AU - Velegol, Darrell

AU - Sen, Ayusman

PY - 2018/10/30

Y1 - 2018/10/30

N2 - Enzymes show two distinct transport behaviors in the presence of their substrates in solution. First, their diffusivity enhances with an increasing substrate concentration. In addition, enzymes perform directional motion toward regions with a high substrate concentration, termed as chemotaxis. While a variety of enzymes has been shown to undergo chemotaxis, there remains a lack of quantitative understanding of the phenomenon. Here, we derive a general expression for the active movement of an enzyme in a concentration gradient of its substrate. The proposed model takes into account both the substrate-binding and catalytic turnover step, as well as the enhanced diffusion of the enzyme. We have experimentally measured the chemotaxis of a fast and a slow enzyme: urease under catalytic conditions and hexokinase for both full catalysis and for simple noncatalytic substrate binding. There is good agreement between the proposed model and the experiments. The model is general, has no adjustable parameters, and only requires three experimentally defined constants to quantify chemotaxis: enzyme-substrate binding affinity (Kd), Michaelis-Menten constant (KM), and level of diffusion enhancement in the associated substrate (α).

AB - Enzymes show two distinct transport behaviors in the presence of their substrates in solution. First, their diffusivity enhances with an increasing substrate concentration. In addition, enzymes perform directional motion toward regions with a high substrate concentration, termed as chemotaxis. While a variety of enzymes has been shown to undergo chemotaxis, there remains a lack of quantitative understanding of the phenomenon. Here, we derive a general expression for the active movement of an enzyme in a concentration gradient of its substrate. The proposed model takes into account both the substrate-binding and catalytic turnover step, as well as the enhanced diffusion of the enzyme. We have experimentally measured the chemotaxis of a fast and a slow enzyme: urease under catalytic conditions and hexokinase for both full catalysis and for simple noncatalytic substrate binding. There is good agreement between the proposed model and the experiments. The model is general, has no adjustable parameters, and only requires three experimentally defined constants to quantify chemotaxis: enzyme-substrate binding affinity (Kd), Michaelis-Menten constant (KM), and level of diffusion enhancement in the associated substrate (α).

UR - http://www.scopus.com/inward/record.url?scp=85054323727&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85054323727&partnerID=8YFLogxK

U2 - 10.1021/acs.biochem.8b00801

DO - 10.1021/acs.biochem.8b00801

M3 - Article

C2 - 30251529

AN - SCOPUS:85054323727

VL - 57

SP - 6256

EP - 6263

JO - Biochemistry

JF - Biochemistry

SN - 0006-2960

IS - 43

ER -