{
  "abstract": "Cytochrome P450 (CYP) monooxygenases are heme-thiolate enzymes that catalyze diverse oxidative transformations essential to metabolism, detoxification, and biosynthesis. While most CYPs rely on separate redox partner proteins for electron delivery, a subset-known as self-sufficient or fusion P450s-incorporate the reductase domain(s) directly within a single polypeptide, enabling efficient intramolecular electron transfer and, in some cases, exceptionally high catalytic turnover. This review examines two representative self-sufficient P450 systems, CYP102A1 (P450 BM3) and CYP116B, summarizing spectroscopic evidence (UV-Vis, EPR, and resonance Raman), supported by available crystal structures, to compare how their distinct domain architectures shape heme electronic structure and catalytic mechanism. CYP102A1, a fused FAD/FMN-heme flavocytochrome from Bacillus megaterium, undergoes pronounced substrate-induced conformational rearrangement and low-spin/highspin switching, properties that are further tunable through active-site mutagenesis (e.g., A82F, F87V, F393 variants) and that underlie its status as the most extensively studied and engineered P450 scaffold. In contrast, CYP116B enzymes, which transfer electrons through a defined FMN-[2Fe–2S]-heme pathway, maintain a comparatively rigid, conserved low-spin heme environment that is less dynamically coupled to substrate binding, although engineered variants (e.g., CYP116B5-SOX) demonstrate their potential for peroxide-driven biocatalysis. Together, these comparisons illustrate how differences in fusion architecture translate into distinct strategies for electron transfer and catalytic control, offering complementary design principlesstructural plasticity in BM3 versus a stable redox scaffold in CYP116B-for engineering nextgeneration self-sufficient P450 biocatalysts.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": null,
  "author_total": 4,
  "authors": [
    {
      "name": "Sravya Vungarala"
    },
    {
      "name": "Mason Daras"
    },
    {
      "name": "Yasmine Elshoweikh"
    },
    {
      "name": "Yilin Liu",
      "orcid": "0000-0003-0213-3993"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/9s0tq1rdj8q33.bib",
  "cited_by": 0,
  "doi": "10.26434/chemrxiv.15009513/v1",
  "fulltext_url": null,
  "id": "9s0tq1rdj8q33",
  "issns": [],
  "landing_url": "https://chemrxiv.org/doi/full/10.26434/chemrxiv.15009513/v1",
  "language": null,
  "licence": "CC-BY",
  "licence_label": "CC BY",
  "licence_source": "journal",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "openalex",
      "1604|Metal-Catalyzed Oxygenation Mechanisms"
    ]
  ],
  "openalex": "W7214667562",
  "pdf_url": "https://chemrxiv.org/doi/pdf/10.26434/chemrxiv.15009513/v1",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-28",
  "publisher": "American Chemical Society (ACS)",
  "ris": "https://research.draconitic.com/paper/9s0tq1rdj8q33.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:17:21Z",
      "native_id": "10.26434/chemrxiv.15009513",
      "source": "chemrxiv",
      "url": "https://chemrxiv.org/doi/full/10.26434/chemrxiv.15009513/v1"
    }
  ],
  "subjects": [
    {
      "field": "chemistry",
      "origin": "openalex:1604|Metal-Catalyzed Oxygenation Mechanisms",
      "subfield": "inorganic"
    }
  ],
  "title": "Structural and Spectroscopic Characterization of Self-Sufficient Cytochrome P450 Fusion Enzymes: CYP102A1 and CYP116B",
  "title_text": "Structural and Spectroscopic Characterization of Self-Sufficient Cytochrome P450 Fusion Enzymes: CYP102A1 and CYP116B",
  "type": "preprint",
  "updated_at": "2026-10-30T12:17:21Z",
  "url": "https://research.draconitic.com/paper/9s0tq1rdj8q33",
  "venue": "ChemRxiv",
  "versions": []
}