{
  "abstract": "The microbial degradation of natural rubber (NR), which is mainly composed of cis-1,4-polyisoprene, is a promising sustainable strategy for rubber waste treatment. In rubber-degrading actinomycetes, the polymer is cleaved by the latex-clearing protein (Lcp) into oligo-isoprene aldehydes (OIA), which are then oxidized and channeled into the β-oxidation pathway. Some strains employ heterodimeric molybdenum hydroxylases (OxiAB) for this oxidation, whereas others, including Gordonia and Nocardia strains, lack oxiA/oxiB adjacent to lcp and instead use NAD(P)+-dependent aldehyde dehydrogenases (ALDHs); however, the ALDH repertoire differs among strains. Here, we identified the ALDHs responsible for OIA oxidation in Rhodococcus sp. RDE2. Cell-free extracts oxidized OIA preferentially with NAD+, although substantial NADP+-dependent activity (~37% of the NAD+-dependent activity) was also detected. Neither activity was induced during NR growth. Six candidate ALDHs were selected by combining homology searches, qRT-PCR, and heterologous expression analyses in Escherichia coli. Among the purified candidates, only LPH33_RS08240 and LPH33_RS17900 exhibited substantial NAD+-dependent OIA-oxidizing activity, which was 2.0- and 1.3-fold higher than that of the reference VH2 ALDH (GPOL_c02580), respectively. Deletion of either gene reduced both NR and OIA oxidation activities, identifying these two enzymes as major contributors to NAD+-dependent OIA oxidation in RDE2 and, to our knowledge, as the first OIA-oxidizing ALDHs identified in the genus Rhodococcus. Double knockouts did not abolish these activities, indicating contributions from additional ALDHs, consistent with the NADP+-dependent activities detected for the three other candidates. These findings extend the OIA-oxidizing ALDH repertoire of rubber-degrading actinomycetes and provide a foundation for engineering rubber-derived bioconversion.\n\nKey points: LPH33_RS08240 and RS17900 are the first OIA-oxidizing ALDHs found in Rhodococcus.\n\nDeleting both genes lowers rubber growth and OIA activity without abolishing either.\n\nNADP+-linked ALDHs may couple rubber degradation to reductive biosynthesis in RDE2.\n\nSupplementary Information: The online version contains supplementary material available at https://doi.org/10.1007/s00253-026-13993-w.",
  "abstract_shown": true,
  "affiliations": [
    "Department of Materials Science and Bioengineering, Nagaoka University of Technology, Nagaoka, Niigata 940-2188 Japan",
    "Department of Bioresources Engineering, National Institute of Technology, Okinawa College, Nago, Okinawa 905-2192 Japan",
    "Escuela de Ingeniería en Biotecnología, Centro de Biotecnología, Universidad Católica del Maule, Talca, Chile"
  ],
  "article_type": "research article",
  "arxiv": null,
  "author_total": 4,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Yukimura Kawagiwa"
    },
    {
      "affs": [
        0,
        1
      ],
      "name": "Namiko Gibu"
    },
    {
      "affs": [
        2
      ],
      "name": "Rodrigo Andler"
    },
    {
      "affs": [
        0
      ],
      "name": "Daisuke Kasai",
      "orcid": "0000-0001-9495-7740"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/ab4h209cc71c7.bib",
  "cited_by": 0,
  "doi": "10.1007/s00253-026-13993-w",
  "fulltext_url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC13737355/",
  "id": "ab4h209cc71c7",
  "issns": [
    "0175-7598",
    "1432-0614"
  ],
  "landing_url": "https://doi.org/10.1007/s00253-026-13993-w",
  "language": "en",
  "licence": "CC-BY-NC-ND-4.0",
  "licence_label": "CC BY-NC-ND 4.0",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by-nc-nd/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "heading",
      "Research"
    ],
    [
      "openalex",
      "2310|Microbial bioremediation and biosurfactants"
    ]
  ],
  "openalex": "W7201967604",
  "pdf_url": null,
  "pmcid": "PMC13737355",
  "pmid": "42983101",
  "published": "2026-08-08",
  "publisher": "Springer",
  "ris": "https://research.draconitic.com/paper/ab4h209cc71c7.ris",
  "sources": [
    {
      "first_seen": "2026-11-09T12:22:34Z",
      "native_id": "PMC13737355",
      "source": "pmc",
      "url": "https://doi.org/10.1007/s00253-026-13993-w"
    }
  ],
  "subjects": [
    {
      "field": "earth",
      "origin": "openalex:2310|Microbial bioremediation and biosurfactants",
      "subfield": "environmental-science"
    }
  ],
  "title": "Aldehyde dehydrogenases for oligo-isoprene aldehyde oxidation in Rhodococcus sp. RDE2",
  "title_text": "Aldehyde dehydrogenases for oligo-isoprene aldehyde oxidation in Rhodococcus sp. RDE2",
  "type": "peer-reviewed",
  "updated_at": "2026-11-09T12:22:34Z",
  "url": "https://research.draconitic.com/paper/ab4h209cc71c7",
  "venue": "Applied Microbiology and Biotechnology",
  "versions": []
}