Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2025 Jun 7;24(1):132.
doi: 10.1186/s12934-025-02751-8.

Vitamin K (Menaquinone) from marine Kocuria sp. RAM1: optimization, characterization and potential in vitro biological activities

Rasha A Metwally  1 , Nermeen A El-Sersy  2 , Amany El Sikaily  3 , Soraya A Sabry  4 , Hanan A Ghozlan  4
Affiliations

Vitamin K (Menaquinone) from marine Kocuria sp. RAM1: optimization, characterization and potential in vitro biological activities

Rasha A Metwally et al. Microb Cell Fact. .

Abstract

Background: Menaquinone (MK), which is also known as vitamin K2, is a kind of lipoquinone that, unlike humans, is biosynthesized in bacteria through a series of steps as a necessary component of their respiratory chain for electron transport among various components of the bacterial cell membrane. MKs are receiving increasing attention as they play several essential biological roles in humans.

Results: In this study, MK was obtained from Kocuria sp. RAM1, characterized using UV absorbance, and validated using nuclear magnetic resonance spectroscopy (NMR) and liquid chromatography-electrospray ionization-quadrupole time-of-flight mass spectrometry (LC-ESI-QTOF-MS). The chemical characterization revealed a total of six MK analogues that were identified and confirmed as MK-1, MK-3, MK-5 (H2), MK-7 (H6), MK-8 (H2), and MK-9. Subsequent to the execution of a significant optimization model, a total KMs of 394.69 µg/ml was obtained, with the MK-1 analog being the dominant one. The antibacterial, anti-inflammatory, antioxidant, anticancer, antidiabetic, and wound-healing activities of MKs were evaluated in vitro. As a result, we discovered that MKs have promising findings on the tested in vitro activities.

Conclusions: Our study was made to evaluate MKs obtained from the Red Sea Kocuria sp. RAM1 to emphasize their significant role in different biological applications. Therefore, from a therapeutic and medicinal perspective, the extracted MKs are interesting for additional in vivo studies.

Keywords: Kocuria; Anti-inflammatory; Anticancer; Antidiabetic; Antimicrobial; Antioxidant; Menaquinone; Wound healing.

PubMed Disclaimer

Conflict of interest statement

Declarations. Consent for publication: The authors declare that they know the content of this manuscript and have agreed to submit it to “Microbial Cell Factories”. Competing interests: The authors declare no competing interests.

Figures

Fig. 1
Fig. 1
Schematic diagram of MK biosynthesis
Fig. 2
Fig. 2
Schematic diagram for MIC and MBC of MK
Fig. 3
Fig. 3
Kocuria sp. RAM1 MK extraction and purification (A). UV–Vis spectroscopy (B)
Fig. 4
Fig. 4
1−HNMR analysis of Kocuria sp. RAM1 MK
Fig. 5
Fig. 5
LC-QTOF-MS analysis of Kocuria sp. RAM1 of MK (A). Mass of MK derivatives (B)
Fig. 6
Fig. 6
The chemical structures of MK analogs produced by Kocuria sp. RAM1
Fig. 7
Fig. 7
Effect of MK on wound closure on HSF (A) and OEC (B) cells every 24 h. Mean ± SD (n=3) is represented in the data
See this image and copyright information in PMC

Similar articles

See all similar articles

References

    1. Nobel Prize for Physiology and Medicine for 1943: Profs. H. Dam and E. A. Doisy. Nature. 1944; 154: 602. 10.1038/154602c0
    1. Dam H, Glavind J. Alimentary exudative diathesis, a consequence of E-avitaminosis. Nature. 1939;143:810–1. 10.1038/143810a0.
    1. Borjigin T, Feng J, Schmitt M, Zhu D, Morlet-Savary F, Xiao P, Lalevée J. Photoinitiators from bio-sourced naphthoquinone–the application of naphthoquinone-based vitamins K1 and K3 in free radical photopolymerization. Green Chem. 2024;26:277–86. 10.1039/d3gc03551d.
    1. Koehn JT, Crick DC, Crans DC. Synthesis and characterization of partially and fully saturated menaquinone derivatives. ACS Omega. 2018;3:14889–901. 10.1021/acsomega.8b02620. - PMC - PubMed
    1. Upadhyay A, Fontes FL, Gonzalez-Juarrero M, McNeil MR, Crans DC, Jackson M, Crick DC. Partial saturation of menaquinone in Mycobacterium tuberculosis: function and essentiality of a novel reductase. MenJ ACS cent sci. 2015;1:292–302. 10.1021/acscentsci.5b00212. - PMC - PubMed

MeSH terms