Frontiers in Microbiology Formatting Requirements: Complete Author Guide

Frontiers in Microbiology uses an unstructured but content-rich abstract format.

• Word limit: 350 words for Original Research and Reviews; 200 words for Brief Research Reports and Mini Reviews
• Structure: Unstructured single paragraph
• Citations: Not allowed in the abstract
• Keywords: 5 to 8 keywords required, listed after the abstract. At least one keyword must be from the Frontiers keyword list for the target section
• Abbreviations: Avoid if possible; define at first use if necessary

The 350-word abstract is significantly more generous than most journals (Nature gives you 150, Elsevier journals typically give 200). Use this space wisely. You can provide real methodological detail and specific quantitative results.

Frontiers keywords have a practical function beyond indexing. They feed into the Frontiers recommendation engine and help the editorial office match your paper with reviewers. Choose keywords that are specific enough to attract the right reviewers but broad enough to be discoverable.

Frontiers has specific formatting requirements for figures that differ from some other publishers.

Figure specifications:

The 15-item cap on combined figures and tables for Original Research is a real constraint. If you're writing a comprehensive study with extensive characterization, plan your figures carefully. Multi-panel figures help. A single figure with panels (A) through (F) counts as one item.

Frontiers-specific figure rules:

• Figures must be embedded in the manuscript at first submission
• Figure captions go below the figure
• Multi-panel figures use uppercase letters: (A), (B), (C) (not lowercase like some other publishers)
• Frontiers prefers figures at the end of the manuscript during review, embedded near their citation point in the final version
• Color is free (online-only journal)

Tables should be created in Word or LaTeX table environments, not submitted as images. Frontiers table format uses minimal horizontal lines and no vertical lines. A header row with a horizontal rule, then data rows, then a bottom rule.

Frontiers uses the Harvard author-date citation system, which sets it apart from numbered-reference journals.

In-text citations: Parenthetical author-date format: (Smith, 2024) for one author, (Smith and Jones, 2024) for two, (Smith et al., 2024) for three or more. Multiple citations are separated by semicolons and ordered chronologically: (Smith, 2020; Jones, 2022; Brown et al., 2024).

Reference list format (alphabetical):

Smith, J. K., Jones, A. B., and Brown, C. D. (2024). Title of article. Full Journal Name 45, 123-130. doi: 10.xxxx/xxxxx

Key formatting specifics:

• Author names: Surname, initials (e.g., "Smith, J. K.")
• "and" before the last author (not "&")
• Year in parentheses after authors
• Article title in sentence case
• Full journal names (not abbreviated). Write "Frontiers in Microbiology" not "Front. Microbiol."
• Volume number in bold, followed by page range or article number
• DOI required for all references that have one
• For books: Author (Year). Title. City: Publisher.

The full journal name requirement is shared with MDPI journals but catches Frontiers authors off guard too. Citation managers often default to abbreviated journal names. Switch your citation manager to "Frontiers" style and verify every reference.

There's no formal cap on references. Original Research articles typically cite 40 to 70 sources. Reviews can go to 100+ without issue.

Frontiers provides a structured system for supplementary material.

Common supplementary content for Frontiers in Microbiology:

• Extended sequence data and phylogenetic trees
• Additional microscopy images
• Full datasets (metabolomics, transcriptomics)
• Detailed protocols and materials lists
• Videos of experimental procedures or dynamic processes

Supplementary material is uploaded through the Frontiers submission system. Files must be cited in the main text as "Supplementary Figure S1" or "Supplementary Table S1."

Frontiers hosts all supplementary files alongside the article. They're open access and available to all readers. The supplementary material goes through peer review.

For large datasets (sequencing data, metabolomics), deposit in appropriate public repositories (NCBI, EBI, MetaboLights) and cite the accession number. Frontiers in Microbiology specifically requires that sequence data be deposited in GenBank, EMBL, or DDBJ with accession numbers provided in the manuscript.

Data availability statement: Required. Must appear as a specific section in the manuscript, specifying where data is available and how to access it.

Supplementary Presentations: Frontiers allows Supplementary Presentations (PowerPoint files) as supplementary material. This is uncommon among publishers but can be useful for complex methodological overviews.

These are Frontiers-specific details that experienced authors know:

Interactive review process. Frontiers uses a unique collaborative review model. After reviewers submit their initial reports, the authors respond through a discussion forum on the Frontiers platform. This back-and-forth continues until consensus is reached. Reviewer identities are disclosed upon publication. The interactive format means your responses to reviewers are visible to both reviewers and the editor simultaneously.

Specialty section selection matters. Frontiers in Microbiology has over 20 specialty sections. Your section choice determines which editor handles the paper and which reviewer pool is accessed. Choosing the wrong section can lead to mismatched reviewers. Check the section scope descriptions carefully before submitting.

Mandatory sections in specific order. Frontiers enforces section order strictly: Abstract, Introduction, Materials and Methods, Results, Discussion (or Results and Discussion combined), Conclusion, Author Contributions, Funding, Acknowledgments, Conflict of Interest, Data Availability Statement, Supplementary Material, References. The template arranges these, and the production team will reject rearranged manuscripts.

Ethics statements. Required for all research involving human subjects, animals, or potentially harmful organisms. The ethics section must include the name of the approving committee and the approval number. For microbiology work with BSL-2+ organisms, biosafety details should be included in Methods.

Author contributions are published. Not just required but published as part of the article. Every author's specific contribution is visible to readers. Use CRediT-style descriptions.

Conflict of interest statement is published. Even "no conflict" declarations appear in the published article.

These come up repeatedly in Frontiers submissions:

1. Full journal names in references. Same issue as MDPI. Citation managers default to abbreviations. Switch to Frontiers style and check manually.

1. Figure/table legends count toward word limit. This surprises authors used to Elsevier or Springer journals where legends are excluded. Budget your words accordingly.

1. Uppercase panel labels. Frontiers uses (A), (B), (C) for multi-panel figures, not (a), (b), (c). This inconsistency with other publishers catches authors who reuse figures from previous publications.

1. Template compliance at initial submission. No free-format first submissions. Use the Frontiers template from the start.

1. Data deposition for sequences. All nucleotide and protein sequences must be deposited in GenBank/EMBL/DDBJ. Accession numbers must be in the manuscript at submission. Reviewers need them to evaluate the data.

In our pre-submission review work with manuscripts targeting Frontiers in Microbiology, four patterns generate the most consistent desk-rejection outcomes.

Clinical framing that omits microbial mechanism. Frontiers in Microbiology covers the microbial side of host-pathogen and host-microbiome interactions, not the clinical management side. The author guidelines specify that Original Research must "advance understanding of microorganisms." Manuscripts framed primarily around patient outcomes or clinical endpoints, with microbial data as supporting context rather than the central subject, are rejected at initial editorial assessment. Editors look for the mechanistic microbiology question in the title and abstract. If the primary question is therapeutic rather than mechanistic, the paper belongs in a clinical journal.

Purely descriptive studies without hypothesis testing or mechanistic interpretation. Frontiers editors apply a "significance and contribution" screen at initial check. Descriptive surveys of microbial community composition, 16S rRNA profiling papers that report diversity indices without testing a mechanistic hypothesis, or characterization studies that stop at "X was different between groups" without explaining why or what mechanism drives the difference are the most common category rejected without review. The author guidelines ask authors to state "what question does this address and why does it matter to microbiology." If the study design doesn't produce testable data on a mechanism, the paper will not pass editorial assessment.

Conclusions that exceed what the experimental data support. Frontiers uses a collaborative review model in which reviewers communicate through an open forum, and reviewer comments on overclaimed conclusions are among the most common revision categories. A metagenomic study of 40 samples cannot conclude that a specific microbiome composition "is a biomarker for X disease." Papers where the abstract conclusion is two logical steps ahead of the data presented in the results section receive major revision requests that are difficult to address without additional experiments.

Specialty section mismatch. Frontiers in Microbiology has more than 20 specialty sections, and the section you select determines which editor handles the manuscript and which reviewer pool is activated. A paper on antimicrobial resistance mechanisms submitted to the Microbial Physiology and Metabolism section, or a food fermentation study submitted to Infectious Agents and Disease, will be redirected or desk rejected for misfit. Review each section's scope description before submitting. The section editor's research area is published on the Frontiers website; if their work does not intersect with your topic, you are in the wrong section.

A Frontiers in Microbiology submission readiness check evaluates whether your manuscript's mechanistic framing, hypothesis clarity, and section assignment match these editorial requirements before peer review begins.