Information für die Wissenschaft Nr. 63 | 7. September 2022

Priority Programme “CodeChi – Chitin, Chitosan and Chito-oligosaccharides and their Interaction with Proteins of the Extracellular Matrix and Cellular Signaling” (SPP 2416)

In March 2022, the Senate of the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) established the Priority Programme “CodeChi – Chitin, Chitosan and Chito-oligosaccharides and their Interaction with Proteins of the Extracellular Matrix and Cellular Signaling” (SPP 2416). This programme is designed to run for six years, and the present call invites proposals from researchers working in this field to join for the first three-year funding period.

Aims and Scope of the Programme

Chitin and chitosans (C/CS) are among the most abundant and versatile polymers in nature, occurring as structural components in numerous types of extracellular matrices, such as arthropod cuticles and hydrogel-like peritrophic matrices or fungal cell walls. The structural tenets underlying the immense range of different physicomechanical properties covered by these extracellular matrices are currently unknown. Equally, C/CS biosynthesis, assembly and degradation during development, differentiation and morphogenesis as well as their interactions with other cellular components and their involvement in the communication between organisms are poorly understood. Based on emerging new evidence, we strongly believe that the molecular fine structure of C/CS (e. g. degree of polymerisation; the degree and pattern of acetylation), contributes to define the properties of C/CS-containing biological matrices and functional materials. In addition, C/CS-binding receptors of human, animal and plant immune systems trigger defence reactions upon perception of C/CS oligomers (COS) produced by the action of C/CS-degrading enzymes. Thus, we hypothesise that the fine-structure of C/CS and COS harbours a code, which we term “CodeChi” (referring to the Greek letter “chi”, which stands for chito), that is “written”, “enacted” and “interpreted” by a large variety of C/CS-binding and C/CS-modifying proteins in organisms that produce these polymers, as well as C/CS-degrading enzymes and C/CS-binding receptors in environmental hosts that perceive C/CS-containing organisms. The Priority Programme aims to decrypt Codec, to understand the molecular and biophysical principles of C/CS functions in nature and to utilise this knowledge for the fabrication of functional materials.

Successful proposals will contribute to the overall scientific objectives of the Priority Programme by addressing the role of CodeChi in the regulation of C/CS biosynthesis and degradation, the design principles of C/CS-containing extracellular matrices, the structure-function relationship of C/CS-interacting enzymes and other C/CS-interacting proteins, including receptors and their involvement in C/CS-triggered immune/defense systems. Specific questions to be addressed are:

Writing CodeChi:

  • How is C/CS biosynthesis and modification regulated by chitin synthases and chitin deacetylases, yielding C/CS with different, defined degrees of polymerisation and degrees and patterns of acetylation?
  • How is C/CS degradation regulated by C/CS-degrading enzymes in biological systems or in the environment, yielding COS with different, defined degrees of polymerisation and degrees and patterns of acetylation?
  • What are the variations in specificity and kinetics between different C/CS-synthesising, C/CS-modifying and C/CS-degrading enzymes, and how do these variations contribute to generating CodeChi in C/CS and COS?

Enacting CodeChi:

  • How is the assembly of different C/CS-containing extracellular matrices regulated by C/CS-synthesising enzymes, C/CS-binding proteins and, possibly, C/CS-modifying and C/CS-degrading enzymes, and how are these processes dependent on CodeChi?
  • How are the structural organisation and functional properties of various C/CS-containing extracellular matrices regulated by interaction with different C/CS-binding proteins, and how are these interactions defined by CodeChi?
  • What are the variations in specificity and kinetics between different C/CS-binding proteins, and how are these variations dependent on CodeChi?

Interpreting CodeChi:

  • How is the generation of defined COS or its avoidance regulated by the interaction of C/CS and C/CS-degrading enzymes in host organisms, and how are these processes dependent on CodeChi?
  • How is the perception of defined COS and the triggering of immune reactions in plants, animals and humans regulated by C/CS receptors, and how are these processes dependent on CodeChi?
  • What are the variations in specificity and kinetics between different C/CS-degrading enzymes and C/CS binding receptors, and how are these variations dependent on CodeChi?

Analysing and utilising CodeChi:

  • Improvement of methods for the chemical or biotechnological synthesis and the structural analysis of C/CS and COS with defined degrees of polymerisation and degrees and patterns of acetylation.
  • Development of methods for the detection and characterisation of C/CS and COS in complex biosamples and of their interactions with proteins in silico, in vitro and in vivo.
  • Bottom-up reconstitution of C/CS-based structures with defined physical, chemical and biological properties and functionalities, rendering them suitable for functional, e. g. biomedical or agricultural applications.

For further details on the research topic, you may contact the coordinator to receive a copy of the proposal that built the basis for the DFG Senate’s approval to install this Priority Programme. Proposals that are not considered in the scope of this Priority Programme are projects with descriptive approaches of only identifying new C/CS-synthesising, -modifying or -degrading enzymes, C/CS-binding proteins or receptors, or projects such as synthetic approaches only focusing on the fabrication or use of C/CS or C/CS-based materials without implementing CodeChi.

Scientific Community

A major goal of the Priority Programme is to bring together scientists from different research areas including disciplines from Life Sciences, Chemistry and Materials Sciences. Fostering the exchange between these disciplines will lead to tangible interdisciplinary cooperation, knowledge transfer between project partners and to the creation of synergies within the consortium. Individual projects should explore in-depth at least one of the key questions and provide substantial information relevant for other projects of the consortium. To strengthen the interdisciplinary character of the Priority Programme, we very much encourage submission of joint projects of two principal investigators from different fields. We also particularly invite outstanding young scientists eligible for DFG funding to submit proposals for individual projects. We will seek to implement projects which, beyond pursuing their own research questions, will provide specific expertise and service to other projects of the consortium. These may include projects which provide core methodological expertise in synthesising and analysing C/CS, COS and C/CS-based materials with defined structures, and characterising the interactions of C/CS and COS with different types of proteins in silico, in vitro and in vivo. Scientists who wish to contribute or make use of this core infrastructure and expertise are encouraged and strongly advised to contact the coordinator (see below) well in advance of the preparatory meeting and the submission deadline.

To ensure the highest scientific quality standards, we will establish an international advisory committee with one leading scientist for each discipline represented in the Priority Programme. The following networking activities are planned: annual internal symposia, seminar series on a monthly basis, status seminars, topical meetings, annual summer schools and interdisciplinary workshops (at international conferences). We provide support to young scientists at various stages of their career and offer family-friendly policies. We seek to increase the proportion of women scientist in the field for which we have placed various targeted measures. All activities of the consortium will be coordinated on an internet platform, supported by the IT infrastructure of the University of Siegen. Our programme will also be visible on social media to promote the network participants’ visibility.

Preparatory Meeting

Scientists who are interested in submitting a proposal for an individual or a joint project in the first funding period are invited to a preparatory meeting hosted by the programme committee and held on 7 October 2022, which will take place online. In this meeting, the background and the organisational structure of the Priority Programme will be presented. Furthermore, breakout sessions will facilitate networking amongst potential applicants. Participation in this meeting is not a prerequisite, but it is highly recommended for the submission of proposals in the scope of this programme. Scientists who are interested are requested to register by 1 October 2022 with the coordinator by email stating “Preparatory Meeting SPP 2416” in the subject line. We encourage all interested parties to submit a short outline of the project idea together with the contact data, a summary of expertise and 2–3 references of important articles. These data will be made accessible to all registered members of the consortium via a protected area of the SPP’s website (see below).

Proposal Submission

Proposals must be written in English and submitted to the DFG by 17 January 2023. Please note that proposals can only be submitted via elan, the DFG’s electronic proposal processing system. To enter a new project within the existing Priority Programme, go to Proposal Submission – New Project/Draft Proposal – Priority Programmes and then select “SPP 2416” from the current list of calls.

In preparing your proposal, please review the programme guidelines (form 50.05, section B) and follow the proposal preparation instructions (form 54.01). These forms can either be downloaded from the DFG website or accessed through the elan portal.

Applicants must be registered in elan prior to submitting a proposal to DFG. If you have not yet registered, please note that you must do so by 10 January 2023 to submit a proposal under this call; registration requests received after this time cannot be considered. You will normally receive a confirmation of your registration by the next working day. Note that you will be asked to select the appropriate Priority Programme call during both the registration and the proposal submission process.

It is planned to evaluate all proposals by a review panel in end of March 2023. All applicants will be informed in due course.

The envisaged start of funding is summer 2023.

Further Information

More information on the Priority Programme is available under the website of SPP 2416:

The elan system can be accessed at:

DFG forms 50.05 and 54.01 can be downloaded at:

For scientific enquiries please contact the Priority Programme coordinator:

  • Professor Dr. Hans Merzendorfer
    Universität Siegen
    Fakultät IV, Institut für Biologie, Abteilung Molekularbiologie
    Adolf-Reichwein-Straße 2
    57076 Siegen
    phone +49 271 740 3917

Questions on the DFG proposal process can be directed to:

Programme contact:

Administrative contact: