I have not participated actively in this bulletin board up to now although
as one of the founders of the BTK group I follow the correspondence with a
mixture of interest and astonishment. However, after reading Douglas Kell's
recent contribution I felt I should bring to the group's attention some
publications to set the record straight. Douglas is right about the
pioneering work on synthetic membrane-bound enzymes, except that it was done
by Ephraim Katchalski and collaborators in the early 60's. In fact I believe
that the first paper to describe the kinetic properties of such a system was
one that I coauthored with Katchalski, Kedem, Silman, and Goldman. We
studied the properties of membrane bound papain both experimentally and
theoretically, and eventually showed that the system might be expected to
exhibit oscillatory behaviour under certain circumstances. Later Danny
Thomas joined my lab for a brief period and succeeded in realizing the
oscillations in vitro. The following series of papers describe some of the
early investigations:
Goldman, R., Silman, H.I., Caplan, S.R., Kedem, O. and Katchalski,
E. Papain membrane on a collodion matrix: Preparation and enzymic
behavior. Science 150, 758-760 (1965).
Blumenthal, R., Caplan, S.R. and Kedem, O. The coupling of an
enzymatic reaction to transmembrane flow of electric current in a
synthetic "active transport" system. Biophys. J. 7, 735-757
(1967).
Goldman, R., Kedem, O., Silman, I.H., Caplan, S.R. and Katchalski,
E. Papain-collodion membranes: I. Preparation and properties.
Biochemistry 7, 486-500 (1968).
DeSimone, J.A. and Caplan, S.R. Symmetry and the stationary state
behaviour of enzyme membranes. J. Theoret. Biol. 39, 523-544
(1973).
DeSimone, J.A. and Caplan, S.R. The determination of local
reaction and diffusion parameters of enzyme membranes from global
measurements. Biochemistry 12, 3032-3039 (1973).
Caplan, S.R., Naparstek, A. and Zabusky, N.J. Chemical
oscillations in a membrane. Nature 245, 364-366 (1973).
Naparstek, A., Thomas, D. and Caplan, S.R. An experimental
enzyme-membrane oscillator. Biochim. Biophys. Acta 323, 643-646
(1973).
I hope this is helpful!
Roy Caplan
S. Roy Caplan (Prof. Emeritus)
Dept. of Biological Chemistry, Weizmann Institute, Rehovot;
Dept. of Physiology, McGill University, Montreal.
Email: rcaplan at med.mcgill.ca
URL: www.cnd.mcgill.ca/people.html
-----Original Message-----
From: "Douglas Kell" <dbk at aber.ac.uk>
To: btk-mca at hgmp.mrc.ac.uk <btk-mca at hgmp.mrc.ac.uk>
Date: Tuesday, August 22, 2000 6:45 PM
Subject: Re: Garfinkel et al. (was Re: Is it Metabolic Control THEORY orM
Some of the pioneering work on this was done by Katchalsky,
Katchalsky-Katzir and collaborators in the 70s, a major conclusion
being that Km(app) or S0.5(app) can be significantly raised over the
'solution' values when the enzyme is bound to a membrane. The effect
is somewhat similar to the concentration polarisation
recognised/described in the fields of electrochemistry and membrane
filtration - as Clause says the Chem Eng literature is where a lot
of this stuiff is found. Also look out in 70s and early 80s for
papers on this by D. Thomas and colleagues at Univ. Compiegne.
Best wishes,
Douglas.
> Petr, the alternative, more rigorous approach to membrane-bound
> enzyme kinetics originate basically from the Chemical Engineering
> field; it differentiates between intrinsic (microscopic, as in
> solution) and inherent (solely resulting from their physical state)
> properties of immobilized enzymes. The combination of both yields
> the effective properties of the catalytic system (macroscopic, as
> observed out of the black box).
>> The latter, most often dealt-with by most biologists, yield a
> distorted picture of the system's behavior, especially when the
> interpretation of the results is based on a (tacite) assumption that
> "ideal" conditions prevail...
>> If you're interested please refer to this central (relatively
> recent) review:
> *Engasser, J.-M. and C. Horvath (1976). Appl. Biochem. Bioeng. 1:127-220.
>> A fascinating discussion, pertaining to the effective consequences
> of enzyme organization can also be found at:
> *Ricard, J., N. Kellershohn, et al. (1989). Spatial order as a source of
> kinetic cooperativity in organized bound enzyme systems. Biophys J
> 56:477-487.
>> The modelling of these aspects is tough and refractive to automation
> due to the non-linearity of the underlying phenomenological
> differential equations. I'd love to see packages like 'gepasi',
> 'biokin', 'jarnac' etc. (sorry I can't enumerate all...),
> implementing that.
>> Some of my (and many cited others') work using localized probes
> deals with the "diagnosis", demonstration and discussion of
> heterogeneous effects in cellular catalysis:
>> *Aflalo, C. and N. Shavit (1984). A new approach to the mechanism of
> photophosphorylation: modulation of ATP synthetase activity by
> limited diffusibility of nucleotides near the enzyme. Curr. Top.
> Cell. Regul. 24: 435-445.
>> *Aflalo, C. and M. DeLuca (1987). Continuous monitoring of ATP in the
> microenvironment of immobilized enzymes by firefly luciferase.
> Biochemistry 26:3913-3919.
>> *Aflalo, C. (1991). Biologically localized firefly luciferase: a tool to
> study cellular processes. Int. Rev. Cytol. 130:269-323.
>> *Aflalo, C. and L. A. Segel (1992). Local probes and heterogeneous
> catalysis: a case study of a mitochondria-luciferase-hexokinase
> coupled system. J. Theor. Biol. 158:67-108.
>> *Aflalo, C. (1997). Localized firefly luciferase probes ATP at the surface
> of mitochondria. J. Bioenerg. Biomembr. 29:549-559.
>> Sincerely,
>> Claude
>> Claude Aflalo ########################## Phones: Office
> 972-7-6472118 #### Unit for Science Teaching/Dept. of Life Sciences
> Lab 972-7-6472119 Ben Gurion University of the Negev
> Fax 972-7-6472890 P.O.Box 653 email:
>aflaloc at bgumail.bgu.ac.il Beer Sheva 84105 Israel ### URL:
>http://www.bgu.ac.il/~aflaloc/aflalo.html>>>> ---
>>>(Prof.) Douglas B. Kell, Cledwyn Building,
Institute of Biological Sciences, University of Wales,
Aberystwyth SY23 3DD
Tel: +44 1970 622334 Fax: +44 1970 622354
dbk at aber.ac.ukhttp://gepasi.dbs.aber.ac.uk/home.htm
---
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