---
DOAJ_listed: '1'
OA_place: publisher
OA_type: gold
_id: '22254'
abstract:
- lang: eng
  text: The global rise of antimicrobial resistance has intensified the search for
    new microbial metabolites from underexplored environments and taxonomic groups.
    Extreme and geographically isolated habitats such as Antarctic terrestrial ecosystems
    represent promising reservoirs of biosynthetic diversity, particularly among rare
    and difficult-to-cultivate actinomycetes that may produce chemically diverse metabolites
    with potential biotechnological applications. Here, we report the characterization
    of kineochelins, a previously undescribed group of siderophores produced by the
    Antarctic isolate Actinokineospora sp. UV203, representing a difficult-to-cultivate
    actinomycete lineage. Structural elucidation revealed a set of closely related
    congeners with a mixed-ligand architecture consistent with metal-chelating activity.
    Genome mining combined with transcriptomic analysis identified a dedicated nonribosomal
    peptide synthetase-encoding biosynthetic gene cluster responsible for kineochelin
    production. Comparative genomic analyses indicated that, although kineochelin
    biosynthetic genes share limited similarity with known mixed-ligand siderophores,
    their gene content and organization differ substantially, suggesting a distinct
    biosynthetic lineage. Functional characterization of the culture supernatant and
    an enriched pre-purified kineochelin fraction demonstrated strong and selective
    iron chelation, with high affinity for ferric and ferrous iron. Crude culture
    extracts inhibited the growth of bacterial strains isolated from the same Antarctic
    environment, indicating that kineochelins may contribute to iron-mediated microbial
    competition. In addition, kineochelin-enriched pre-purified fractions showed moderate
    selective inhibitory activity against the opportunistic yeast pathogen Nakaseomyces
    glabratus and a clinical isolate of Saccharomyces cerevisiae associated with invasive
    infection. These findings expand the chemical and biosynthetic diversity known
    within the genus Actinokineospora and demonstrate that Antarctic rare actinomycetes
    represent valuable sources of previously unexplored natural products. The discovery
    of kineochelins highlights the potential of genome-guided exploration of polar
    microorganisms for identifying bioactive metabolites with relevance for antimicrobial
    discovery and biotechnology.
acknowledgement: This work was supported by the Czech Antarctic Research Programme
  2025–2027 (VAN 2025) and the University of Vienna via the Research Platform Secondary
  Metabolomes of Bacterial Communities (MetaBac). S.K. has received funding from the
  European Union's Horizon 2020 research and innovation programme under the Marie
  Skłodowska-Curie grant agreement No. 101020356 (DEFCOMANT, https://doi.org/10.3030/101020356)
  and MASH StG/CoG (MUNI/SC/1946/2024) by Masaryk University. T.R. and A.L. were funded
  in part by the Austrian Science Fund FWF [grant DOI https://doi.org/10.55776/COE7].
  M.B. was funded by the Ministry of Health, Czech Republic—conceptual development
  of research organization (FNBr, 65269705). The Life Science Compute Cluster LiSC
  at the University of Vienna provided the high-performance computing infrastructure
  for this study. We thank Julia Ramesmayer and Sara Malinowski (Joint Microbiome
  Facility of the Medical University of Vienna and the University of Vienna) for assistance
  during high molecular weight extraction and RNA extraction. The authors thank Anna
  Fabisikova and Michael Klemm-Abraham from the Mass Spectrometry Centre and the team
  of the NMR Centre (both core facilities of the Faculty of Chemistry, University
  of Vienna, and members of the Vienna Life Science Instruments) for assistance with
  data acquisition. We are thankful to Dr. Jaime Felipe Guerrero Garzón for helpful
  discussions on the use of a rrn operon promoter strategy. For open access purposes,
  the authors have applied for a CC BY public copyright licence to any author-accepted
  manuscript version arising from this submission. Dr. Martin Kello (Department of
  Pharmacology, Faculty of Medicine, Pavol Jozef Šafárik University, Košice, Slovakia)
  and Dr. Michal Goga (Department of Plant Biology, Faculty of Science and Center
  for Interdisciplinary Biosciences, Technology and Innovation Park, Pavol Jozef Šafárik
  University in Košice, Košice, Slovakia), funded by VEGA 1/0498/23, are acknowledged
  for their assistance with the antiproliferative assays. This work was supported
  by Horizon 2020 Framework Programme, 101020356; Universität Wien, MetaBac; Ministry
  of Education, Youth and Sports, VAN 2025; Masarykova Univerzita, MUNI/SC/1946/2024;
  Austrian Science Fund, 10.55776/COE7; Ministerstvo Zdravotnictví České Republiky,
  FNBr, 65269705; Vedecká grantová agentúra Ministerstva školstva, výskumu, vývoja
  a mládeže Slovenskej republiky a Slovenskej akadémie vied, VEGA 1/0498/23.
article_number: e70386
article_processing_charge: Yes
article_type: original
author:
- first_name: Stanislava
  full_name: Kralova, Stanislava
  last_name: Kralova
- first_name: Peter
  full_name: Spacek, Peter
  last_name: Spacek
- first_name: Johannes
  full_name: Gafriller, Johannes
  last_name: Gafriller
- first_name: Matej
  full_name: Bezdicek, Matej
  last_name: Bezdicek
- first_name: Viktoria
  full_name: Medvedcova, Viktoria
  last_name: Medvedcova
- first_name: Joana
  full_name: Séneca, Joana
  last_name: Séneca
- first_name: Jay
  full_name: Osvatic, Jay
  last_name: Osvatic
- first_name: Ulrike
  full_name: Grienke, Ulrike
  last_name: Grienke
- first_name: Thomas
  full_name: Rattei, Thomas
  last_name: Rattei
- first_name: Olga N.
  full_name: Sekurova, Olga N.
  last_name: Sekurova
- first_name: Sergey B.
  full_name: Zotchev, Sergey B.
  last_name: Zotchev
- first_name: Martin
  full_name: Zehl, Martin
  id: 8e016d5b-5d77-11f0-86d2-96cdb3922a55
  last_name: Zehl
  orcid: 0000-0001-9685-0373
- first_name: Alexander
  full_name: Loy, Alexander
  last_name: Loy
biorxivid: 1
citation:
  ama: Kralova S, Spacek P, Gafriller J, et al. Kineochelins - A new group of siderophores
    from an antarctic bacterium. <i>Microbial Biotechnology</i>. 2026;19(6). doi:<a
    href="https://doi.org/10.1111/1751-7915.70386">10.1111/1751-7915.70386</a>
  apa: Kralova, S., Spacek, P., Gafriller, J., Bezdicek, M., Medvedcova, V., Séneca,
    J., … Loy, A. (2026). Kineochelins - A new group of siderophores from an antarctic
    bacterium. <i>Microbial Biotechnology</i>. Wiley. <a href="https://doi.org/10.1111/1751-7915.70386">https://doi.org/10.1111/1751-7915.70386</a>
  chicago: Kralova, Stanislava, Peter Spacek, Johannes Gafriller, Matej Bezdicek,
    Viktoria Medvedcova, Joana Séneca, Jay Osvatic, et al. “Kineochelins - A New Group
    of Siderophores from an Antarctic Bacterium.” <i>Microbial Biotechnology</i>.
    Wiley, 2026. <a href="https://doi.org/10.1111/1751-7915.70386">https://doi.org/10.1111/1751-7915.70386</a>.
  ieee: S. Kralova <i>et al.</i>, “Kineochelins - A new group of siderophores from
    an antarctic bacterium,” <i>Microbial Biotechnology</i>, vol. 19, no. 6. Wiley,
    2026.
  ista: Kralova S, Spacek P, Gafriller J, Bezdicek M, Medvedcova V, Séneca J, Osvatic
    J, Grienke U, Rattei T, Sekurova ON, Zotchev SB, Zehl M, Loy A. 2026. Kineochelins
    - A new group of siderophores from an antarctic bacterium. Microbial Biotechnology.
    19(6), e70386.
  mla: Kralova, Stanislava, et al. “Kineochelins - A New Group of Siderophores from
    an Antarctic Bacterium.” <i>Microbial Biotechnology</i>, vol. 19, no. 6, e70386,
    Wiley, 2026, doi:<a href="https://doi.org/10.1111/1751-7915.70386">10.1111/1751-7915.70386</a>.
  short: S. Kralova, P. Spacek, J. Gafriller, M. Bezdicek, V. Medvedcova, J. Séneca,
    J. Osvatic, U. Grienke, T. Rattei, O.N. Sekurova, S.B. Zotchev, M. Zehl, A. Loy,
    Microbial Biotechnology 19 (2026).
corr_author: '1'
das_tickbox: '1'
dataavailabilitystatement: The genome sequence and transcriptomic data of strain Actinokineospora
  sp. UV203 are available on NCBI (BioProject accession number PRJNA1331526). The
  nearly full-length 16S rRNA gene (1395 bp) of strain Actinokineospora sp. UV203
  is available on NCBI (accession number PX090945). The NMR data of kineochelin E1
  and A1 are deposited in the Natural Products Magnetic Resonance Database (NP-MRD)
  under accession numbers NP0352113 and NP0352114, respectively.
date_created: 2026-07-08T09:19:43Z
date_published: 2026-06-01T00:00:00Z
date_updated: 2026-07-13T06:59:08Z
day: '01'
ddc:
- '570'
department:
- _id: MassSpec
doi: 10.1111/1751-7915.70386
external_id:
  biorxivid:
  - 10.64898/2026.02.23.707395
  pmid:
  - '42210522'
file:
- access_level: open_access
  checksum: 4f735714644f1049b22b014225843d8d
  content_type: application/pdf
  creator: dernst
  date_created: 2026-07-13T06:57:19Z
  date_updated: 2026-07-13T06:57:19Z
  file_id: '22271'
  file_name: 2026_MicrobialBiotechnology_Kralova.pdf
  file_size: 2497486
  relation: main_file
  success: 1
file_date_updated: 2026-07-13T06:57:19Z
has_accepted_license: '1'
intvolume: '        19'
issue: '6'
keyword:
- Actinokineospora
- Antarctica
- antimicrobial discovery
- biosynthetic gene cluster
- genome mining
- microbial competition
- nonribosomalpeptide synthetase
- siderophores
language:
- iso: eng
month: '06'
oa: 1
oa_version: Published Version
pmid: 1
publication: Microbial Biotechnology
publication_identifier:
  eissn:
  - 1751-7915
publication_status: published
publisher: Wiley
quality_controlled: '1'
scopus_import: '1'
status: public
supplementarymaterial: yes
title: Kineochelins - A new group of siderophores from an antarctic bacterium
tmp:
  image: /images/cc_by.png
  legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
  name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
  short: CC BY (4.0)
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 19
year: '2026'
...