Identification and Characterization of Bioactive Microbial Metabolites for Advancing Research on Microbe-Diet-Host Interactions (R01 Clinical Trial Not Allowed) | PAR 21 253

Opportunity Information: Apply for PAR 21 253

The NIH funding opportunity PAR 21 253, titled "Identification and Characterization of Bioactive Microbial Metabolites for Advancing Research on Microbe-Diet-Host Interactions (R01 Clinical Trial Not Allowed)," supports research projects aimed at discovering and rigorously characterizing microbial metabolites that directly influence host biology. The central goal is to move beyond simple correlations between the microbiome and health outcomes by generating evidence that links specific microbial metabolic activities and the molecules they produce to causal effects on host health and disease. Projects funded under this announcement are expected to produce high-quality, well-annotated data that can clarify how microbe-derived small molecules mediate microbe-diet-host interactions, including how dietary inputs are transformed by microbes into compounds that affect host physiology.

A major feature of this announcement is that it is not just about individual lab discoveries; it is also building shared infrastructure for the broader scientific community. Data generated by funded projects will feed into a publicly accessible knowledgebase of microbial metabolites and their associated functions. That knowledgebase and its web portal are to be developed and maintained through a companion initiative, RFA-DK-21-014, which funds a separate Knowledgebase Management Center using a U24 cooperative agreement mechanism. In practice, this means successful R01 applicants should anticipate that their outputs will need to be structured, well-documented, and suitable for integration into a community resource, helping standardize and accelerate future work in microbiome metabolite biology.

The award mechanism is an NIH R01 research project grant, and clinical trials are not allowed under this particular solicitation. The overall program sits at the intersection of food and nutrition, environment, and health research, aligning with NIH interests in understanding mechanistic pathways by which microbial metabolism and diet-derived substrates influence host outcomes. The opportunity is listed under multiple CFDA numbers (93.113, 93.121, 93.393, 93.396, 93.847, 93.855), reflecting involvement or relevance across several NIH institutes and centers that support complementary areas of biomedical and nutrition-related research.

Eligibility is broad and includes many types of U.S.-based organizations. Eligible applicants include state, county, city, township, and special district governments; independent school districts; public and state-controlled institutions of higher education; private institutions of higher education; federally recognized Native American tribal governments; tribal organizations that are not federally recognized; public housing authorities and Indian housing authorities; nonprofits with and without 501(c)(3) status (excluding institutions of higher education where applicable); for-profit organizations (other than small businesses); and small businesses. The announcement also explicitly highlights additional eligible applicant categories such as Alaska Native and Native Hawaiian Serving Institutions, Asian American Native American Pacific Islander Serving Institutions (AANAPISI), Hispanic-serving Institutions, Historically Black Colleges and Universities (HBCUs), Tribally Controlled Colleges and Universities (TCCUs), faith-based or community-based organizations, eligible federal agencies, regional organizations, and U.S. territories or possessions.

At the same time, there are clear restrictions around foreign applicants. Non-domestic (non-U.S.) entities and non-domestic (non-U.S.) institutions are not eligible to apply as the applicant organization, and non-domestic components of U.S. organizations are not eligible to apply. However, foreign components are allowed as defined by the NIH Grants Policy Statement, meaning a U.S.-based applicant may include certain well-justified international elements or collaborations within NIH policy limits, even though the primary applicant organization must be domestic.

Key administrative details include the agency (National Institutes of Health), the opportunity category (discretionary), the instrument type (grant), and the original closing date of 2023-10-19, with the FOA created on 2021-07-06. The notice does not specify an award ceiling or expected number of awards in the provided text, so applicants generally would need to consult the full NIH posting for budgeting norms, institute-specific priorities, and any additional review considerations. Overall, this FOA is designed for research teams positioned to connect microbial chemistry to host biology in a way that yields mechanistic insight and produces reusable, standardized metabolite-function information that can be shared widely through a dedicated community knowledge portal.

• The National Institutes of Health in the education, environment, food and nutrition, health sector is offering a public funding opportunity titled "Identification and Characterization of Bioactive Microbial Metabolites for Advancing Research on Microbe-Diet-Host Interactions (R01 Clinical Trial Not Allowed)" and is now available to receive applicants.
• Interested and eligible applicants and submit their applications by referencing the CFDA number(s): 93.113, 93.121, 93.393, 93.396, 93.847, 93.855.
• This funding opportunity was created on 2021-07-06.
• Applicants must submit their applications by 2023-10-19. (Agency may still review applications by suitable applicants for the remaining/unused allocated funding in 2026.)
• Eligible applicants include: State governments, County governments, City or township governments, Special district governments, Independent school districts, Public and State controlled institutions of higher education, Native American tribal governments (Federally recognized), Public housing authorities/Indian housing authorities, Native American tribal organizations (other than Federally recognized tribal governments), Nonprofits having a 501 (c) (3) status with the IRS, other than institutions of higher education, Nonprofits that do not have a 501 (c) (3) status with the IRS, other than institutions of higher education, Private institutions of higher education, For-profit organizations other than small businesses, Small businesses, Others.

Apply for PAR 21 253

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