Objective
A.GENERAL BACKGROUND
A.1: Why a COST Action on this topic
Compared to non-enzymatic chemical catalysts, biocatalysts (enzymes or whole-cell microorganisms) are known to present some interesting and advantageous features: high efficiency, mild environmentally-friendly operation conditions, versatility and, last but not least, high selectivity (chemo-, regio- and stereoselectivity). The selectivity and particularly the stereochemical properties observed when biocatalysts act on their natural substrates, if extended to the usual objects of organic synthesis, may be of outstanding interest for the preparation of the enantiopure compounds now required for use as drugs and agrochemicals. In recent years the influence of the chemical industry on the environment has been in focus. Now the term "Green Chemistry" is used for the technology "that reduces or eliminates the use or generation of hazardous substances in the design, manufacture and application of chemical products" (Paul Anastas and John Warner). Introduction of biocatalytic processes will certainly contribute in this respect.
There is both general and industrial interest in further research in biocatalysis for organic chemistry, and a collaboration of organic chemists, biochemists and molecular geneticists is needed for success. The development of biocatalytic methodologies undoubtedly involves a strong cooperation of these researchers for extending the scope of enzyme activities and reactions, the search for better catalysts, the extensive use of modern methods for protein engineering and the process optimisation including downstream processing. The use of biocatalysts in chemical industry is clearly an activity within the field of biotechnology.
Such a COST-coordinated action should probably strengthen the competitivity of European laboratories and companies versus Japan or the US.
The key importance of the interdisciplinary field centred on the development of stereoselective biocatalytic reactions has been previously recognised within COST Action D2 (Selective Synthesis 1992-1997), and subsequently within COST Action D12 (Organic Transformations: selective processes and Asymmetric Catalysis), with participation of many working groups. There are currently about 100 laboratories from 21 countries organised in 20 working groups within the COST D12 programme which carry out research on various aspects of stereoselective synthesis. In light of the fact that this very successful action will be terminated in 2002, this justifies the launch of a new COST action on "Applied Biocatalysis", with the objective of coordinating future efforts by the participating groups and, possibly, new research teams working in this area on topics of timely and relevant interest.
Finally, there is a large interest from the pharmaceutical and fine-chemical industry to collaborate with academia on the development of new catalytic processes. This is evident from the COST D12 programme where several working groups have established fruitful collaborations with companies such as: CIBA, Novartis, AstraZeneca, Pharmacia Inc. and Degussa. A new COST action in the field of biocatalytic reactions would certainly further strengthen and expand collaborations to include other European companies such as BASF, DSM and Lonza. As opposed to more traditional chemical industry, biocatalytic processes often require less expensive equipment and therefore is well suited for smaller companies.
A.2: Status of the research in the field
The use of growing cells in order to catalyse chemical reactions is not new. However, the use of pure enzymes or cells, in aqueous or organic media, in order to catalyse specific organic reactions, biotransformations, has emerged in recent years. This field of research is at present undergoing rapid development. The importance of biocatalysis both in research and industry has been emphasised in a series of review articles in the journal Nature of 11 January 2001. Several important examples of applications of biocatalysts in the chemical process industry are available such as:
-Microbial transformation of acrylonitrile into acrylamide in a large industrial scale (>30,000 tons/year)
-Enzymatic synthesis of bioactive carbohydrates, glycoconjugates, glycolipids.
-Enzymatic synthesis of unnatural alfa- and beta-amino acids
-The use of hydrolytic enzymes in reverse hydrolysis conditions (synthesis of peptides, glycosides, phosphates, beta-lactames)
-Replacement of established chemical steps by environmentally friendly enzymatic catalysis in industrial synthesis
European laboratories already constitute centres of excellence in this field, but some needs of coordination for their activities and the necessary transfer of knowledge to the industrial world still exist. For this reason, a new COST action would help to bring together experts from academic laboratories working on the methodology of biocatalyst selection and their application to synthetic reactions and strategies. Groups from industry will join and thus gain expertise in the use and scaling-up of these reactions when relevant to industrial development.
A.3: Relationship with other European Programs
Several conference series, both on a world wide international scale, with visible European participation, and on a European level have been set up to encourage scientific exchange in the field of biocatalysis. These are:
(i)European Federation of Biotechnology, Section for Applied Biocatalysis (ESAB) (next in Trondheim June 2001)
(ii)Biannual "Biotrans" (Next in Darmstadt Sept. 2001)
(iii)Biannual Chiral Europe (and Biannual Chiral USA)
(iv)Nordic, French/Italian and other regional Biocatalysis Conferences.
Furthermore, during the years 1989-1994 the EU project "Characterisation of lipases for industrial applications" provided structures of several new lipases, which became available to the scientific community.
B.OBJECTIVES OF THE ACTION AND SCIENTIFIC CONTENT
B.1: Main objective
The main objective of the Action is to develop new biocatalytic reactions with special emphasis on stereoselectivity and environmentally friendly processes. This objective will be pursued by providing new biocatalysts and new biocatalytic processes.
This COST Action will coordinate new joint research efforts and strengthen existing ones in the interdisciplinary field of biocatalysis. The wide field of biocatalysis will ideally comprise researchers from areas such as microbiology, enzymology, molecular biology structural biology and organic chemistry. Promotion of more intensive scientific exchange between individual groups, particularly those with complementary expertise, will be beneficial for European research and lead to a stronger impact of this research in a rapidly growing field. It is expected that the proposed Action will be attractive also for industrial research groups interested in production of enantiopure chiral building blocks.
While the detailed scientific programme will depend on the projects submitted (se below), there is a will to encourage participation in certain priority areas, which appear to be of particular importance for the progress of the field. These priority areas are outlined in the following sub-topics, which report proposed research activities, by a number of potential participants to this Action.
As a consequence of this action we expect a substantial development of chemo-enzymatic methods to produce chiral building blocks and moreover, better understanding of biocatalytic processes.
B.2: Sub-topics
The success of a biocatalytic reaction is dependent on three factors: (1) the catalyst, (2) the substrate and (3) the medium of the reaction. The goal of the research will be two-sided: (a) synthesis of particular target molecules (chiral building blocks) and (b) better understanding of the biocatalytic process.
In order to obtain chiral building blocks there are three different possibilities: (i) start synthesis from a cheap natural product (sugars, terpenoids, amino acids etc.), (ii) perform an asymmetric synthesis starting with a prochiral or a meso-compound or (iii) perform a resolution of a racemic mixture. Apart from (i) the research performed under the Action will contain all of these aspects.
(a)Production of chiral building blocks
Why are today's chemists concerned about stereospecificity in their work? This has to do with the structure of many organic molecules. Some molecules exhibit what is known as handedness in their structure, they are chiral. A pair of molecules may be related to one another like the left hand to the right hand. They are mirror images and called enantiomers. Enantiomers are identical when they are in a symmetrical environment. They have the same physical properties such as melting point and boiling point and cannot be separated by, for example, distillation. Under standard conditions in the laboratory, when chemists attempt to synthesise them, equal amounts of each enantiomer, is formed.
In a process involving synthesis of enantiopure target molecules, it is of utmost importance for the efficiency to introduce correct stereochemistry as early as possible. As mentioned above, chiral building blocks, which very often are small or medium-sized compounds, often with a secondary oxygen function at the stereocenter, can be produced catalytically by enzymes either by asymmetric synthesis or racemate resolution. Both strategies have their pros and cons; the advantage of kinetic resolution is that high enantiomeric excess can always be achieved if yield can be sacrificed. The disadvantage is that the maximum yield of one enantiomer is 50%. However, this disadvantage can be overcome if the reaction is performed as dynamic kinetic resolution, or by an additional inversion reaction. Asymmetric synthesis may give 100% yield of one enantiomer, however, under sub-optimal conditions, it is difficult to influence on the course of the reaction. This sub-topic, production of chiral building blocks, will be an important part of the Action.
(b)Chemo-enzymatic synthesis of chiral drugs
When enantiomers are in an asymmetric environment, they are different. This is particularly important when drugs are chiral. Just as the left hand glove fits badly on the right hand and vice versa, enantiomers of drugs behave differently in the body. This difference may be more or less significant. In the most drastic cases, the "wrong" enantiomer of a drug may give serious side effects. The wrong enantiomer of an anaesthetic drug may give hallucinations or, like the drug Thalidomide, give rise to birth defects. Enzymes or whole cells have the ability to catalyse chemical reactions in a stereospecific manner and in this way lead to synthesis of only one form of a drug.
Drugs that are chiral have to be marketed as single enantiomers. This is valid not only for drugs that currently are on the market, but also for new ones. Single isomers of chiral drugs are currently sold for more than 100 billion US dollars and this figure is expected to rise (Chemical & Engineering News, 23 October 2000). It will be a sub-topic of the Action to demonstrate that biocatalysis can play a part in the synthesis of chiral drugs.
(c)Development of new biocatalysts
At present several useful enzymes are commercially available. Due to their ease of operation, hydrolytic enzymes are most frequently used, but oxido-reductases and aldolases (lyases) are also very important. Since enzymes are proteins, they may be produced by fermentation. The producing organism may be manipulated in order to give a tailor made catalyst for a particular process. This activity involves molecular biology and preferably knowledge of structure of enzymes. For some reactions the use of whole cells may be attractive. This in particular, implies oxidations and reductions. An important sub-topic of the COST-action will be providing new catalysts, either new organisms or new enzymes.
(d)Medium engineering and immobilisation
The reaction medium is very often important for the catalytic process. It may be water, but very often an organic medium. If it is water there are not many possibilities of influencing the medium. On the other hand, if organic media are used, the choice of solvent will significantly influence both the rate and selectivity of the process. Moreover, the content of water, expressed by the water activity, in the medium is of importance.
In some cases it may be attractive to immobilise a biocatalyst. This may be performed in different ways. For organic chemical synthesis, immobilisation is often performed by binding the catalyst to a solid support. Immobilisation will simplify the operation of biocatalysts in a reactor. However, immobilisation also gives the catalyst new properties.
Optimisation of biocatalytic processes by medium engineering and immobilisation will be an important sub-topic.
(e)Structural and mechanistic studies of enzymes
In order fully to understand a biocatalytic process and thus in turn optimise it, purification and structure elucidation of the enzyme is desirable. Whether this is realisable or not, will depend on the working groups participating in the Action.
(f)Implementations of biocatalysis in industry
Several biocatalytic processes are at present well established in industry. However, development of new processes will be needed. It will be an important sub-topic to include producers of fine chemicals or pharmaceuticals in the Action.
C.ORGANISATION MANAGEMENT AND RESPONSIBILITIES
C.1: Organisation and Management
Research projects fitting topics mentioned above will be submitted to the Management Committee for approval. Approval will be subject to the evaluation of their relevance for the establishment of sustainable chemical processes of interest for the European member countries.
C.2: Responsibilities
The Management Committee has responsibilities for:
1.Drawing up the inventory during the first year, organisation of workshops and start of the activity; existing contacts will be used which should greatly facilitate this task.
2.Coordination of the joint activities with other COST Actions, CEFIC Sustech Clusters; joint meetings are likely to result from this activity.
3.Exploring the possibilities for wider participation and exchange of information with EU specific programmes, ESF, EUREKA, etc.
4.Planning the intermediate report, the final report and the concluding symposium.
Progress reports will also be provided by each respective participant in the projects in their own countries within the framework of existing programmes.
C.3: Evaluation of Progress
The progress of the programme will be monitored by means of brief annual reports from each of the participating scientists. These will describe the results of research obtained through concerted action. The Management Committee will prepare a milestone report after 2 years of joint activities. The report will be presented to the COST Technical Committee for Chemistry for their review and to the COST Senior Officials Committee for information. A final report will be published to inform non-participating scientists and research workers interested in the results about the scientific achievements of the Action. It is expected that some review by participants, which describe the progress, made and state of the field, will be published in international journals. To conclude the COST Action, a symposium will be held after 5 years. It will be accessible to other scientists and potential users of industry.
D.TIMETABLE
The programme will cover five years and consist of the following stages:
Stage 1:After the first meeting of the Management Committee a detailed inventory of on-going research and existing plans of the participating groups to begin joint projects will be made. This will result in a discussion document to allow further planning.
Stage 2:It will be evident which projects are closely related and would benefit from joint activities. Researchers (and co-workers) will set-up (and continue) joint collaborative projects and exchange their recent research results. It may be appropriate to explore wider collaboration with other European countries during this stage.
Stage 3:An intermediate progress report will be prepared after two years for review by the COST Technical Committee for Chemistry and for information to the COST Senior Officials Committee.
Stage 4:This final phase will begin after four years and will involve the evaluation of the results obtained. It may include the organisation of a symposium for all the participants and co-workers. The final report will be submitted to the COST Technical Committee for Chemistry for scientific assessment and after to the COST Senior Officials Committee.
In summary the total timetable can be represented as follows:
-Start 1st year
-Formation of projects 1st and 2nd year
-Workshop of group leaders end of 1st year and each year later on
-Overview available; start meetings; continue meetings on sub-topics end of 2nd year
-Start exploration of wider participation 3rd and 4th year
-Intermediate Progress Report available for Technical Committee and CSO end 2nd year
-Start evaluation of results continuously each year after 1st year at the yearly workshop
-Concluding Symposium end of 5th year.
E.DURATION OF THE ACTION
The Action will last for five years.
Although applied biocatalysis in the present context, is a part of organic chemistry, collaboration with related research fields will be needed. The number of catalysts available commercially is rather limited, and contacts between groups within biochemistry will be ideal in order to discover and develop new catalysts. This will necessarily take time. Moreover, time will be needed in order to identify relevant industrial problems. This will need contact between academia and relevant companies, it will certainly take some time to establish such contacts. Generally, to create strong research groups in order to produce results, it is suggested that the Action last for five years.
F.ECONOMIC DIMENSION OF THE ACTION
It is to be expected that 22 countries will apply for admission to the new COST Action. The 22 countries have actively participated in the preparation of the Action or otherwise indicated their interest.
On the basis of national estimates provided by the representatives of these countries, the overall cost of the activities to be carried out under the Action has been estimated, in 2000 prices at roughly EUR 65 million.
The estimate is valid under the assumption that all these countries but no other countries will participate in the Action. Any departure from this will change the total cost accordingly.
G.DISSEMINATION OF SCIENTIFIC RESULTS
All publications arising from research carried out under COST Action D25 will credit COST support and the Management Committee will encourage and promote all co-authored papers. Results of research carried out by the working groups under COST Action D25 will be submitted to international scientific journals and reviewers.
Joint meetings among different working groups in COST Action D25 and with working groups from other COST Actions, will be organised so as to best promote interdisciplinary communication.
The Management Committee (MC), in conjunction with the working groups (WG) of the Action will meet every year with the main aim of presenting results to the MC as a whole and, where possible, the MC will invite potential users and interested parties to this meeting.
The Management Committee will, during the first year of the Action, also set up a work-plan for interdisciplinary events for the dissemination of results of the Action COST D25.
Also the COST Chemistry web site (http://www.unil.ch/cost/chem) will be exploited for the dissemination.