French Associates Institute for Agriculture and Biotechnology of Drylands,
Jacob Blaustein Institutes for Desert Research (BIDR),
Ben-Gurion University of the Negev, Sde Boqer Campus,
849900 Midreshet Ben-Gurion, Israel
Tel. 972-8-6596817 (office) | 972-8-6596823 (laboratory)
B.Sc.: 1969-1972 Ben-Gurion University, Beer-Sheva. Biology (summa cum laude).
M.Sc.: 1972-1975 Ben-Gurion University, Beer-Sheva. Biology (cum laude).
Advisor: Professor Noun Shavit.
Thesis: On the involvement of adenylate kinase and bound nucleotides in the mechanism of ATP synthesis in isolated chloroplasts.
Ph.D.: 1980-1985 Ben-Gurion University, Beer-Sheva, Israel. Biology.
Advisor: Professor Noun Shavit.
Thesis: On the involvement of tightly bound ATP and concentration gradients of charged reactants near the thylakoid membranes in the mechanism of photophosphorylation.
· Employment History
2003-: Senior lecturer, Inst of Agriculture and Biotechnology, BIDR, BGU.
2001-2003: Senior lecturer, Dept of Biotechnology Engineering, Ben-Gurion University.
1999-2001: Senior lecturer, Unit for Science Teaching, Ben-Gurion University.
1992-1999: Lecturer, Department of Life Sciences, Ben-Gurion University.
1988-1992: Scientist, Dept. of Biochemistry, Weizmann Institute of Science (WIS), Rehovot.
1985-1988: Research assistant (with Prof. M. DeLuca), Department of Chemistry, University of California at San Diego, La Jolla, California, USA.
1980-1985: Instructor in Biochemistry, Department of Biology, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
1975-1980: Military Service. Officer in the Israel Defense Forces.
1979: Research assistant and professional training at the Virology Unit, Soroka Medical Center, Beer Sheva, Israel (Prof. I. Sarov).
1972-1975: Teaching Assistant in Biochemistry, Department of Biology, Ben-Gurion University, Beer-Sheva, Israel.
· Professional Activities
a. Positions in academic administration
1994: Representative of lecturers, Natural Sciences Faculty Council, BGU.
1996-1998: Member, graduate student committee, Dept. of Life Sciences, BGU.
1997: Representative of lecturers, Natural Sciences Faculty Council, BGU.
2001-2003: Director of teaching labs, Dept. of Biotechnology Engineering, BGU
b. Refereeing for Scientific Journals
1994: Referee for Bulletin of Mathematical Biology, L.A. Segel, Ed.
1996: Referee for Langmuir (Am. Chem. Soc.), R.G. Nuzzo, assoc. Ed.
1999: Referee for Analytical Biochemistry, W.S. Allison, assoc. Ed.
1999: Referee for FEBS Letters, G. Semenza, P. Jolles, Eds.
1999: Referee for Cell. Molec. Life Sci., P. Jolles, Ed.
1999: Referee for Bioinformatics Journal, C. Ozounis, assoc. Ed.
2003: Referee for FEMS Lett., J. Cole, Ed.
2006: Referee for Can J Physiol Pharmacol, J. Wigle, assoc. Ed.
2007: Referee for BBA-Prot. Proteomics, P. F. Cook, exec. Ed.
2008: Referee for Journal of Applied Phycology, M. Borowitzka, Ed.
2008: Referee for Applied Microbiology and Biotechnology, K. Watanabe, C. Schmidt-Dannert Eds.
2010: Referee for Journal of Phycology, J Raven, Ed.
c. Advanced courses
1984: FEBS Course 84-02: Redox and Energy Transfer Proteins of Coupling Membranes, Bari, Italy.
1991: Three-dimensional structure of proteins, Prof. Harold Scherraga, Rehovot.
2008: Confocal Laser Scanning Microscopy, Dr. Thomas R. Neu, Sde Boker
· Educational Activities
a. Courses taught
1. Biochemistry A and B (coordinator), undergraduate level, Life Sciences, BGU.
2. Principles of Biochemistry A (coordinator), undergraduate level, Life Sciences, BGU.
3. Proteins and Enzymes: Structure and Function, Life Sciences, Chemistry, BGU.
4. Basic Laboratory of Biochemistry, (coordinator) Life Sciences, BGU.
5. Learning and Teaching Science in a multidisciplinary environment, Science Teaching, BGU.
6. Basic Labs coordination, Biotechnology Engineering, BGU.
b. Research Students
1995-1996: Heftsiba Azoulay, M.Sc. Dept. of Life Sciences.
1996-2000: Heftsiba Azoulay, Ph.D. (Stud. Wolf prize, 1999), Dept. of Life Sciences.
1996-1999: Michael Vinogradov, M.Sc. Dept. of Life Sciences.
1996-1999: Adina Weinberger, M.Sc. (cum laude), Dept. of Life Sciences.
2002-2005: Amir Ferber, M.Sc. (joint advisor with Prof. Boussiba), Dept. of Life Sciences
2004- : Ran Sadeh, M.Sc. Microalgae Laboratory, BIDR
2004-2006: Ro'y Hubashi, M.Sc. Microalgae Laboratory, BIDR
2003-2007: Yoram Hoffman, Ph.D. (joint advisor with Prof. Boussiba) MBL, BIDR.
2007-2009: Lee Recht, M.Sc. (joint advisor with Prof. Boussiba) MBL, BIDR.
2009- : Itamar Avishai, M.Sc., MBL, BIDR.
· Awards, Citations, Honors, Fellowships
a. Honors, Citation Awards
1974: "Delek" award for best student in the Dept. of Biology (BGU).
1982: "Wolf" award for best Ph.D. students in Natural Sciences and Technology in Israel.
1987: Travel award from the National Academy of Science (NRC, USA).
1993: "Teva" research award from Teva Foundation.
1985: "Fulbright" travel award for postdoctoral studies (CIES, USA).
1985: Post doctoral fellowship from NSF (USA, grant # DMB 85-16795), $37,000.
1986: Biotechnology training grant (post doctoral) from the Academic Senate of the University of California, San Diego (#6/786210/19908), $12,000.
1986: International Sepharadi Education Foundation scholarship for post doctoral studies, $1,500.
1988: Feinberg fellowship for scientists (2 years salary at WIS).
1989: Support from Israel Ministry of Integration (one year salary at WIS,+$500).
1991: Support from Fondation RASHI, France (one year salary at the WIS).
1999: Guastalla fellowship (three years salary at BGU) from Fondation Rashi.
· Scientific Publications
a. Chapters in collective volumes
1. N. Shavit, D. Bar-Zvi, O.L. Podhajcer & C. Aflalo, 1981. Role of Tight Nucleotide Binding Sites in the Regulation of the Chloroplast ATP Synthetase Functions in Proceedings of the 5th International Congress on Photosynthesis (G. Akoyunoglou, ed.), Vol. 2, pp. 789-800, Balaban Int. Sci. Ser., Philadelphia.
2. N. Shavit, C. Aflalo & D. Bar-Zvi, 1981. Role of Tight Nucleotide Binding Sites in the Modulation of the Chloroplast ATP Synthetase Activity in Energy Coupling in Photosynthesis (B.R. Selman & S. Selman-Reimer, eds.), pp. 197-207, Elsevier/North Holland, Amsterdam.
3. C. Aflalo & N. Shavit, 1984. Limited Access of Nucleotides to the Active Site of ATP Synthetase During Photophosphorylation in Proceedings of the 6th International Congress on Photosynthesis (C. Sybesma, ed.), Vol. 2, pp. 559-562, Nijhoff/Junk Publishers, The Hague.
4. N. Shavit, C. Aflalo, D. Bar-Zvi & M.A. Tiefert, 1984. Modulation of ATP Synthetase: Conformational States, Nucleotides Binding and Limited Accessibility to the Active Site in Proceedings of the 6th International Congress on Photosynthesis (C. Sybesma, ed.), Vol. 2, pp. 493-500, Nijhoff/Junk Publishers, The Hague.
5. C. Aflalo & N. Shavit, 1984. Involvement of Nucleotides Concentration Gradients in ATP Formation by the Membrane-Bound ATP Synthetase in Reports of the 3rd EBEC Conference (G. Schafer, ed.), pp. 291-292, Congress Edition, Hanover.
6. C. Aflalo, 1993. Monitoring a Heterogeneous Coupled System Using Soluble and Biologically localized Firefly Luciferase as a probe for Bulk and Local [ATP]. Modern Trends in Biothermokinetics (S. Schuster, M. Rigoulet, R. Ouhabi, and J.P. Mazat, eds.), pp. 7-10, Plenum, NY.
7. C. Aflalo, 1994. Biologically localized Firefly Luciferase Probes Local [ATP] at the Surface of Yeast Mitochondria in Biothermokinetics (H.V. Westerhoff, ed.), pp. 345-353, INTERCEPT, Andover, U.K.
8. C. Aflalo, H. Baum, D.M. Chipman, R.E. McCarty, H. Strotmann, 1997. Noun Shavit (1930-1997). Obituary. Photosynth. Res. 54, 165-167.
b. Refereed articles and refereed letters in scientific journals
1. C. Aflalo & N. Shavit, 1976. Phosphorylation of nucleotides bound to chloroplast membranes and their role in photophosphorylation. Biochim. Biophys. Acta 440, 522-530.
2. C. Aflalo & N. Shavit, 1982. Source of rapidly labeled ATP tightly bound to non-catalytic sites on the chloroplast ATP synthetase. Eur. J. Biochem. 126, 61-68.
3. C. Aflalo & N. Shavit, 1983. Steady state kinetics of photophosphorylation: Limited access of nucleotides to the active site on the ATP synthetase. FEBS Lett. 154, 175-179.
4. C. Aflalo & N. Shavit, 1984. A new approach to the mechanism of phosphorylation: modulation of ATP synthetase activity by limited diffusibility of nucleotides near the enzyme. Current Topics in Cellular Regulation 24, 435-445.
5. C. Aflalo & M. DeLuca, 1987. Continuous monitoring of ATP in the microenvironment of immobilized enzymes by firefly luciferase. Biochemistry 26, 3913-3920.
6. C. Aflalo & M. DeLuca, 1988. Continuous monitoring of ATP in the microenvironment of immobilized enzymes by firefly luciferase . Prog Clin Biol Res 273, 337-342.
7. C. Aflalo, 1990. Targeting of cloned firefly luciferase to yeast mitochondria. Biochemistry, 29, 4758-4766.
8. C. Aflalo, 1991. [Invited Review]. Biologically localized firefly luciferase: A tool to study cellular processes. International Reviews in Cytology, 130, 269-323.
9. E. Katchalski-Katzir, I. Shariv, M. Eisenstein, A.A. Friesem, C. Aflalo & I.A. Vakser, 1992. Molecular surface recognition: determination of geometric fit between proteins and their ligands by correlation techniques. Proc. Natl. Acad. Sci. USA. 89, 2195-2199.
10. C. Aflalo & L.A. Segel, 1992. Local probes and heterogeneous catalysis: a case study of a mitochondria-luciferase-hexokinase coupled system. J. Theor. Biol. (cover page of issue) 158, 67-108.
11. I.A. Vakser & C. Aflalo, 1994. Hydrophobic docking: a proposed enhancement to molecular recognition techniques. Proteins: Structure, Function and Genetics, 20, 320-329.
12. L. Gheber, Z. Priel, C. Aflalo & V. Shoshan-Barmatz, 1995. Extracellular ATP binding proteins as potential receptors in mucociliary epithelium: characterization using [32P]3'-O-(4-benzoyl)benzoyl ATP, a photoaffinity label. Molecular Membrane Biology, 147, 83-93.
13. H. Azoulay & C. Aflalo, 1996. [Reviewed article] Binding of hexokinase to mitochondria of various sources. In “Biothermokinetics of the Living Cell" (Westerhoff, H.V., Snoep, J.L., Sluse, F.E., Wijker J.E. & Kholodenko B.N., eds.), pp. 289-294, Biothermokinetics Press, Amsterdam.
14. C. Aflalo & I. A. Vakser, 1996. [Reviewed article] Molecular recognition techniques: geometric docking and its enhancement using hydrophobicity. In “Biothermokinetics of the Living Cell" (Westerhoff, H.V., Snoep, J.L., Sluse, F.E., Wijker J.E. & Kholodenko B.N., eds.), pp. 283-288, Biothermokinetics Press, Amsterdam.
15. E. Katchalski-Katzir, I. Shariv, M. Eisenstein, A.A. Friesem, C. Aflalo & I.A. Vakser, 1996. The role of geometric fit between proteins molecules and their ligands in determining biological specificity. Adv. Molec. Cell Biol., 15B, 623-637.
The Molecular Recognition group at WIS won an international contest (CASP) for the best docking algorithm for prediction of intermolecular protein-protein interactions.
Reference: Strynadka, Eisenstein, Katchalski-Katzir, et al., 1996. Molecular docking programs successfully predict the binding of a lactamase inhibitory protein to TEM-1 -lactamase. Nature-Structural Biology 3 (3), 233-239 (see also Insight article, same Issue).
16. C. Aflalo, 1997. Localized firefly luciferase probes ATP at the surface of mitochondria. J. Bioenerg. Biomembr. 29, 549-559.
17. C. Aflalo & H. Azoulay, 1998. Association of rat brain hexokinase to yeast mitochondria: effect of environmental factors and the source of porin. J. Bioenerg. Biomembr., 30, 245-255.
18. C. Aflalo, W. Bing, A. Zarka & S. Boussiba, 1999. Effect of the herbicide glufosinate (BASTA) on astaxanthin accumulation in the green alga Haematococcus pluvialis. Z. Naturforsch. 54, 49-54.
19. H. Azoulay-Zohar & C. Aflalo, 1999. Binding of rat brain hexokinase to recombinant yeast mitochondria: Identification of necessary molecular determinants. J. Bioenerg. Biomembr., 31, 567-577.
20. H. Azoulay-Zohar & C. Aflalo, 2000. Binding of rat brain hexokinase to recombinant yeast mitochondria: Identification of necessary physico-chemical determinants. Eur J Biochem, 267, 2973-2980.
21. S. Boussiba & C. Aflalo, 2005. An insight into the future of Microalgal Biotechnology. Innovations in Food Technology, 28, 37-39.
22. C. Aflalo, Y. Meshulam, A. Zarka & S. Boussiba, 2007. On the relative efficiency of two vs.one-stage production of astaxanthin by the green alga Haematococcus pluvialis. Biotechnol Bioengin, 98, 300-305.
23. Y. Hoffman, C. Aflalo, A. Zarka, J. Gutman, T. Y. James & S. Boussiba, 2008. Isolation and characterization of a novel chytrid species (phylum Blastocladiomycota), parasitic on the green alga Haematococcus. Mycol Res 112, 70-81.
24. D. Sever, R. Eldor, G.A. Sadoun, L. Amior, D. Dubois, C. Boitard, C. Aflalo, D. Melloul, 2010. Evaluation of Beta Cell Mass and Function in NOD Mouse Model Using Biolumi-nescence Imaging. FASEB J, 25. 676-684.
c. Unrefereed professional articles and publications
1. H. Azoulay & C. Aflalo, 1998. Association of rat brain hexokinase to recombinant yeast mitochondria: effect of environmental factors and the source of porin in Proceedings of Israeli Biochemical Society, Tel Aviv 98.
2. H. Azoulay A. Brieman & C. Aflalo, 1998. Characterization of the heterologous binding between rat brain hexokinase and recombinant porin-containing yeast mitochondria in Proceedings of the Israeli Biochemical Society, Tel Aviv 98.
3. C. Aflalo, A. Zarka, A.K. Singh & S. Boussiba, 1998. Involvement of a Na+/H+ antiporter in pH regulation in the alkaliphilic filamentous cyanobacterium Spirulina platensis in Proceedings of the Israeli Biochemical Society, Tel Aviv 98.
4. A. Weinberger and C. Aflalo, 1998. Heterologous expression of hexokinase, porin and luciferase in yeast: towards a model system for studying mammalian cell metabolism in Proceedings of the second Meeting of FISEB, p. 142.
5. H. Azoulay-Zohar and C. Aflalo, 1998. Binding of rat brain hexokinase to recombinant yeast mitochondria: identification of necessary molecular and physical determinants in Proceedings of the second Meeting of FISEB, p. 143.
6. C. Aflalo, 2009. Microalgae: a promising energy crop? Yes, but a road map is needed. Revue Adapes-Passages, 161, 53-54.
· Lectures and presentations at meetings and invited seminars (last ten years)
a. Invited plenary lectures at conferences/meetings (see ref # in Publications above)
1992: 5th Biothermokinetics Meeting, Bordeaux, France; (a.6)
1993: Gordon Conference, Session leader: Enzyme Organization, Oxnard, CA.
2009: 7th World Forum of Sustainable Development, Jerusalem – June 10-11
2009: ASLO Aquatic Sciences Meeting, Nice, France - January, 25-30
2011: Alg'n'Chem 2011 Algae, new resources for Industry? Montpellier, France
b. Presentation of papers at conferences/meetings
Aflalo, C & Vakser, I. 1994. Hydrophobic docking. 6th Biothermokinetics Meeting, Shroken, Austria. (oral)
Aflalo, C & Vakser, I. 1995. Hydrophobic docking. Gordon Conference: Enzyme Organization, Oxnard, CA. (poster)
Azoulay, H & Aflalo, C. 1995, Coupling between oxidative phosphorylation and hexokinase: channeling of ATP probed by firefly luciferase localized at the surface of mitochondria. First Meeting Israeli Society Experimental Biology, Eilat, Israel. (poster)
Aflalo, C & Vakser, I. 1996. 7th Biothermokinetics Meeting, Louvain la Neuve, Belgium. (poster, see a.14)
Azoulay, H & Aflalo, C. 1996. 7th Biothermokinetics Meeting, Louvain la Neuve, Belgium. (poster, see a.13)
Azoulay, H & Aflalo, C. 1996. Binding of hexokinase to mitochondria. Gordon Conference: Enzyme Organization, Oxford, UK.
Azoulay, H & Aflalo, C; Azoulay, Brieman, H A & Aflalo C; Aflalo, C. Zarka, A., Singh, A.K &. Boussiba, S, 1998. Meeting of the Israeli Biochemistry and Molec. Biol. Society, Tel Aviv. (3 posters see c.1-3)
Aflalo, C & Azoulay H, 1998. Association of rat brain hexokinase to yeast mitochondria Gordon Conference: Enzyme Organization, Oxford, UK. (poster)
1999: 4th Northumbria Assessment Conference, Newcastle, UK. (workshop)
1999: 7th International Improving Student Learning Symposium, York, UK. (workshop)
2000: TICE 2000: IT & Comm. in Educ. for Eng. & Indus., Troyes, France. (workshops)
2001: Gordon Conference: Innovat. College Chem. Teaching, Ventura, CA. (workshops)
2002: Gordon Conference: Oscillat.& Dyn. Instab. in Chem. Systems, Oxford, UK.
2002: Gordon Conference: Macromol. Org. Cell Function, Oxford, UK.
Aflalo, C & Zohar, H, 2003. Molecular and physical dissection of the heterologous association between brain hexokinase and yeast mitochondria. EMBO Workshop: Biological Implications of Macromolecular Crowding, Avila, Spain.
2004: 11th Chlamydomonas International Conference, Kobe, Japan.
Aflalo, C & Boussiba, S, 2006. Cellular factors mediating the production of astaxanthin by Haematococcus pluvialis. 12th International Conference on Cell & Mol. Biol. of Chlamydomonas, Portland, OR. (oral)
Aflalo, C & Boussiba, S, 2007. On the relative efficiency of two-stage vs. one-stage production of astaxanthin by the green microalga Haematococcus pluvialis. 7th Microalgal Biotechnology Workshop, Potsdam, Germany. (oral)
Peled E, Zarka A, Aflalo C & Boussiba S, 2008. Localization of astaxanthin rich oil globules in
Haematococcus pluvialis: a photodynamic process. 11th International Conference on Applied Phycology, Galway Ireland. (oral)
Aflalo C, 2008. Light-dependent proton uptake activity in Haematococcus pluvialis . 11th International Conference on Applied Phycology, Galway Ireland. (poster).
Aflalo C, 2009 7th World Forum of Sustainable Development, Jerusalem – June 10-11 Invited
Aflalo C, 2009 ASLO Aquatic Sciences Meeting, Nice, France - January, 25-30 Invited
Aflalo C, 2010 Insight in microalgal Carbon flux under growth and stress conditions by biomass analysis. 14th International Conference on Cell & Mol. Biol. of Chlamydomonas, Norton, MA. (oral)
Aflalo C, Zarmi Y, 2011. Validity of the steady state 3 states model for photosynthesis to describe microalgal growth in a photobioreactor. 4th Congress of the International Society on Applied Phycology, Halifax, Canada. (poster)
Aflalo C, Zarmi Y, Bel G, 2011. A model for microalgal photosynthesis coupled to random walk in a mixed photobioreactor at high densities. Alg'n'Chem 2011 Algae, new resources for Industry? Montpellier, France. (oral) Invited.
c. Seminars at universities and institutions
1993: Dept. of Physiol. and Pharmacol., School of Medicine, Tel Aviv University.
1993: Department of Chemistry, Ben-Gurion University.
1994: Department of Membrane Research, The Weizmann Institute.
1997: Department of Chemical Engineering, Ben-Gurion University.
1997: Department of Life Sciences, Ben-Gurion University.
1998: Dept. of Life Sciences, BGU, Dept. day: Struc. predictions on the porin fold.
1998: Department of Physiology, University College London, UK.
1999: Department of Biochemistry, Mich. St. Univ. East Lansing, MI.
1999: Department of Biomedical Sciences, Wadsworth Center, Albany, NY.
2004: BIDR, Sde Boker, BGU
2006: BIDR, Sde Boker, BGU
2008: BIDR, Sde Boker, BGU
2009: Laboratoire d'Oceanographie de Villefranche-sur-mer, France
2009: Comore, INRIA-CNRS, Sofia Antipolis, France.
· Research Grants
1987: Research grant from NSF (USA, # DMB 85-16795-A01, joint with Dr. DeLuca). Period of the grant 1987-1989, $90,000 per year, total $270,000.
1994: "Nucleus" research grant from the Dept. of Research & Development, BGU. Period of the grant 1994, total $10,000.
1996: Research grant from the US-Israel Binational Science Foundation, joint with Prof. J.E. Wilson, Michigan State University at East Lansing. Period of the grant 1996-1999, $28,500 per year, estimated total $86,000.
1998: Research grant from the Wellcome Trust, joint with Dr. Luca Turin, Dept of Anatomy, University College, London, UK. Period of the grant 1998, $4,000.
1999: Guastalla fellowship and educational research funding (total $10,000) from Fondation Rashi.
2001: Support from Madarom (Rashi, 3 months for high school student as research assistant).
2009: Algal Biotechnology for Biodiesel Production. Joint with MBL. 1.5 year $780,000 from Thailand Gov.
2010: FP7 - GIAVAP Genetic Improvement of Algae for Value Added Products. 3 years Consortium (13 participants) 7.6MEu from the European Community.
· Synopsis of research (from post-doc 1986; see ref # in Publications above)
(i) Demonstration of basic heterogeneity in cells at the functional level as inferred from that observed at the structural level.
(ii) How cellular processes are controlled and modulated using this heterogeneous organization. This refers to association and segregation of catalytic systems according to metabolic needs, and implies the possibility of dynamic (re)organization.
(iii) The evolution of metabolic organization and its quantitative consequences on the function of living cells.
The following systems have been investigated:
1. Development of cloned firefly luciferase as a tool to measure local ATP concentrations in cells and isolated organelles (yeast). [a.6-7; b.5-8, b.10, b.16] NSF-87.
2. Genetic engineering, cloning and expression of bioluminescent firefly luciferase. [a.6-7, b.7-8] NSF-87.
3. Protein import: luciferase as a reporter for intracellular localization and assembly. [a.6-7, b.7-8] NSF 87.
4. Firefly luciferase mechanism: kinetics of light production. [b.8] NSF-87.
5. Genetic engineering and recombinant expression of mitochondrial porin molecules in yeast. [b.17, b.19, c.1-2] BSF-96.
6. Interaction of rat brain hexokinase with mitochondrial porin from various sources. [b.13, b.17, b.19-20, c.2, c..4-5] Nucleus-94, BSF-96.
7. Involvement of a Na+/H+ transporter in the pH regulation of alkaliphile cyanobacteria (in cooperation with Prof. S. Boussiba, BGU, Sde Boker). [c.3]
8. Biophysical study of the mechano-chemical coupling model for ATP synthesis in the coupling factor of bioenergetic membranes (in cooperation with Dr. Luca Turin, University College London, UK). [unpublished] Wellcome-98.
9. Genomics (sequence-secondary structure relation in porins) and Structural Biology (hydrophobic/geometric surface complementarity in macromolecular association). [unpublished, b.9, b.11, b.14, b.15] Rashi-91.
10. Characterization, simulation and visualization of complex systems: non-linear dynamics, oscillations and pattern formation. [unpublished] Guastella-99.
11. Molecular mechanisms for resistance to herbicides in green algae (in cooperation with Prof. S. Boussiba, BGU, Sde Boker).[b.18]
· Present Academic Activities
Research in progress
Development of basic tools to study green algae metabolism, in cooperation with the members of the Micro-algae Unit in Sde Boker (profs. Boussiba, Vonshak & Cohen. This includes
· molecular biology, towards transformation and genetic engineering of H. pluvialis, with emphasis on cloning and over-expression of heterologous genes (e.g., chloroplast AcCoA synthetase).
· cells fractionation and organelles (chloroplast and mitochondria) isolation, towards algal cellular biochemistry;
· experimental framework for the action and regulation of carotenoids biosynthetic pathway, and its relation with lipid synthesis.
This multifaceted program is starting with my relocation to Sde Boker.
· C. Aflalo, W. Bing, A. Zarka, S. Boussiba, Imbalance in Energy Consumption Regulates Astaxanthin Accumulation in the Green Alga Haematococcus pluvialis.
· A. Zarka, C. Aflalo, A. K. Singh, S. Boussiba, The effect of amiloride on pH regulation in the alkaliphilic filamentous cyanobacterium Spirulina platensis.
· C. Aflalo, A Basic Introduction to Complex Dynamic Systems: I. The maths of spatio-temporal instability, chemical and ecological examples.
· H. Azoulay-Zohar, A. Weinberger & C. Aflalo, Recombinant human porin conveys a high brain hexokinase binding ability to yeast mitochondria.
· A. Brieman, H. Azoulay-Zohar & C. Aflalo, Functional analysis of recombinant yeast expressing natural and mutated wheat porin.
· M. Vinogradov & C. Aflalo, Binding of rat brain hexokinase to recombinant yeast mitochondria: Cross-linking studies of hexokinase and porin.
· A. Weinberger & C. Aflalo, The phenotype of a yeast triple mutant lacking hexose phosphorylation ability cannot be complemented by rat brain hexokinase.
Appendix to CV: Statement of research interests
Structural studies continuously uncover the importance of organization in biological systems at different levels, from molecules to whole organisms. However, many studies of biological function and regulation are performed with isolated systems, in which essential features of the original organization have been altered or lost. This approach forces the experimenter to treat the systems as independent entities for which a set of assumptions apply, but do not necessarily reflect their natural operating conditions. Other approaches involving the macroscopic study of the same systems in their native (non- isolated) state yield global information, which is not readily amenable to interpretation in terms of mechanism of action and control. The comparison of the intrinsic properties of isolated systems with their effective behavior in situ generally indicates a most significant contribution of the native organization.
Although immense progress has been independently achieved in each of these "main stream" aspects, they tend to diverge into separate specialized fields, and no comprehensive approach is presently available to readily integrate the resulting accumulated information. The "missing links" involve two major groups of modulating factors including (i) physical steps (diffusion, chemical or electrostatic partition of reactants) which may be crucial in determining the local operating environment of enzymes in a heterogeneous (as opposed to soluble) system, and (ii) specific interactions between the components of the system among themselves, like in multienzyme clusters, or with other structures such as the cytoskeleton or membranes.
The considerations above apply to all biological systems. While broadly recognized, they are seldom applied or effectively taken into account in functional studies of processes beyond the strictly molecular level. The knowledge of the mode of interaction between systems among which matter or energy is transferred (e.g., reactants, oxido-reduction equivalents, osmotic or mechanical work, signals, etc.), would not only improve significantly the basic understanding of biological function, but also enable the identification and eventually the design of better systems for use in technological applications.
2. Scope and rationales.
Biological organization ("cellular socialism") must lead to various functional consequences, often arbitrarily segregated into qualitative and quantitative aspects. Both relate to observed phenomena that cannot be explained solely on the basis of the behavior in a homogeneous solution, in which the reactants are assumed to be randomly distributed and equally accessible to each other ("molecular democracy").
In the intracellular milieu, the intermediate reactants of a metabolic sequence may be transferred directly between consecutive enzymic components without equilibrating with the ambient medium. This arises from either the existence of a stable enzymatic complexes, or pair-wise transient associations, during which the product of one enzyme is directly transferred to the next one. This phenomenon is reflected experimentally by the lack of availability of the intermediate in solution. It effectively results in an alteration of the expected kinetic properties of the whole pathway, when a simple homogeneous behavior is assumed. Such channeling of intermediates is carried out through molecular recognition between the catalytic components, which involve specific interactions at their respective surfaces. Alternatively, the association of an enzyme with a non-substrate ligand (small molecule, enzyme, or structural element) may result in the allosteric modulation of its catalytic activity.
The reason for the need of such complex mechanisms, too often left aside for philosophers, is probably to promote flexible means for control of cellular processes. Indeed, the possibility of selective channeling of intermediates enables preferential routing of metabolic fluxes through branched pathways, in the crowded cellular environment. In contrast, a freely diffusible intermediate, serving as a substrate to different enzymes randomly distributed in a homogeneous solution, would be subject to simple competition and its fate predetermined by the fixed concentrations of the binding sites. Considering the kinetic mechanism of an enzyme acting in solution, limitation by diffusion is considered as the ultimate criterion for "catalytic perfection". It is a fact that most enzymes considered as soluble did not evolve to reach this exalted status. It is likely that the selective constrains on efficiency relate also to the interactive aspects of the various systems rather than to their performance as independent entities only. Accordingly, optimal cellular function has been attained through the simultaneous evolution of favorable interactions between the systems. Finally, it should be borne in mind that the organization in biological systems is not restricted to space; the components may be dynamically rearranged or interact differently as a response to changes in the ambient conditions according to metabolic needs, and thus operate differently in time.
3. Tools and methodology.
As mentioned in section 1, no established approach is able to address directly the question of functional interaction between related systems in situ, on the basis of their properties observed in vitro after their isolation. One can nevertheless single out proper means to demonstrate and study these interactions.
a. Physical interaction between macromolecules may be predicted from their known structure. Additionally, a reasonably stable interaction can be demonstrated experimentally by physico-chemical techniques
b. Alternatively, the mode and extent of coupling between two processes in situ can be monitored selectively using enzymic probes, which report the concentration of specific reactants. The probes can be targeted to selected cellular compartments by genetic engineering techniques in which the cloned gene encoding for the probe is manipulated so it includes the information necessary for directing the expressed product to the chosen site in intact cells. When the probe molecules are localized at the proper cellular site, local concentrations of reactant can be measured. The resultant information can then be compared with conventional macroscopic measurements of these reactants to diagnose their mode of transfer between the coupled processes.
c. In order to interpret correctly the differences between macroscopic and localized measurements, the various possibilities for non-homogeneous behavior must be identified and properly modeled on the basis of the properties of the systems studied in solution, and taking into account as much as is known of the environmental parameters in effect in situ. The mathematical models help to identify the principles determining the differences in behavior of coupled systems when different modes of coupling are considered. These models can be critically tested experimentally in vitro by reconstitution of the functional coupling between two previously isolated systems (in the broad sense, i.e., enzymes, isolated organelles, or even metabolic pathways in crude extracts). The goal is to reach properties for the reconstituted coupled system, which are comparable to these observed in situ.
Appendix to CV: Statement of teaching interests
To my belief, the conventional undergraduate teaching programs in Cell Biology often suffer from over-emphasis on the structural side at the expense of functional and quantitative aspects. The latter are usually treated in general Biochemistry courses, which, on the other hand, concentrate on isolated systems and tend to underestimate the role of intracellular dynamic organization in living processes.
Consequently, since these two major fields in modern biology have significantly diverged over the last decade, the average, freshly graduated, biologist often must "evolve" in one of these directions, with no sufficient tools to integrate both the approaches.
It seems thus imperative to prepare better the next generation to a multidisciplinary Research and Development environment, which is the preferred way to approach the challenging questions emerging in modern Biology.
• General: Development of better interfaces between mathematics, physics, chemistry and biology teaching at all levels of education (from primary school to graduate research). This includes (i) providing a broader scientific background to students and especially teachers/instructors, by implementing the knowledge of educators in parallel disciplines (e.g., quantitation and modeling in natural sciences for math teachers, applied maths for science teachers, etc.); (ii) promoting a bidirectional transfer of information from specialists in one field to educators in another field (specialists must speak the “language" of the educators); (iii) establishing active, continuing connections and partnerships between individual science teachers and scientists.
• Frame and goals: Continuous planning and adjustment of the curriculum in biotechnology engineering, balancing and tuning the relative contributions of scientific as well as technological disciplines, according to the ever-changing market needs. Reinforcing positive cooperation at the advanced teaching level between lecturers and advisors to mentor short-term joint research projects in complementary fields. This will allow a better mutual recognition of both sides, encouraging scientists to invest more in communicating challenges, methods and results of their own research to the students by providing both opportunities and training. On the other hand, teachers will get familiar with current research approaches, concepts, and technology as well as to experience practical manipulation, critical thinking, and problem-solving skills used in both research and development.
• Specifics aims: This frame may host diverse activities, instrumental in reaching the above mentioned goals and for which much experience has accumulated in both the Faculty of Sciences and Engineering at the undergraduate level: (i) research projects in the specific topics of the scientists' labs; (ii) joint development of interactive, introductory hands-on modules (theory and practice) using complementary input from the lecturers; (iii) joint development of similar modules designed for direct implementation and application in graduate classes; (iv) establishment at the university of a common pool for materials, equipment and instrumentation representing the logistic basis to support practice modules in [ii and iii], and serving as a transferable model.
• Life Sciences: Development of an "interface module" between biochemistry and cell/ molecular biology at the undergraduate level. This includes (i) cellular organization, its consequences on metabolic function and regulation, and mass/energy transfer between cellular (micro-) compartments; (ii) basic concepts in cellular enzymology with emphasis on protein traffic and assembly of cellular and supramolecular structures; (iii) analysis of protein structure by sequence and/or geometric analysis; (iv) development and operation of teaching tools in biochemistry, molecular and cell biology using the Internet as both an information resource and an interactive medium for self- or directed- education