Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Microbial Fermentation01:23

Microbial Fermentation

1.2K
Fermentation is a crucial anaerobic metabolic process that enables microbes to derive energy from sugar without relying on oxygen or an electron transport chain. This process is fundamental to various biological and industrial applications and is classified based on the metabolic products generated.Role of Pyruvate in FermentationPyruvate and its derivatives serve as key electron acceptors in fermentative pathways. The oxidation of NADH to regenerate NAD+ is essential for the continuation of...
1.2K
Microorganisms in Agriculture and Food industry01:27

Microorganisms in Agriculture and Food industry

1.1K
Microorganisms play a crucial role in agriculture and the food industry, contributing to soil fertility, crop protection, and food production. Their functions range from nitrogen fixation and biopesticide production to fermentation and food preservation, making them indispensable to sustainable farming and food safety.Role in AgricultureNitrogen-fixing bacteria, such as Rhizobium (symbiotic) and Azotobacter (free-living), convert atmospheric nitrogen into ammonia through biological nitrogen...
1.1K
Biosynthesis in Bacteria01:24

Biosynthesis in Bacteria

457
Biosynthesis in bacteria is a fundamental anabolic process that generates essential macromolecules, including proteins, nucleic acids, lipids, and polysaccharides. These macromolecules are critical for cellular growth, replication, and function. The process is tightly regulated and energetically linked to catabolic pathways to ensure optimal resource utilization.Biosynthetic pathways begin with precursor metabolites such as pyruvate, acetyl-CoA, and glucose-6-phosphate derived from glycolysis,...
457
Microbial Nutrition01:28

Microbial Nutrition

931
Organisms exhibit remarkable metabolic diversity, categorized based on how they acquire energy and carbon. These strategies enable survival in various ecological niches and are essential for maintaining energy flow and nutrient cycling within ecosystems.Energy and Carbon SourcesOrganisms are classified as phototrophs or chemotrophs based on energy acquisition. Phototrophs use light as their energy source, while chemotrophs rely on oxidizing chemical compounds. Further differentiation arises...
931
Microbial Growth Media01:27

Microbial Growth Media

1.1K
Microbial growth media are essential tools in microbiology, providing the nutrients and conditions necessary to cultivate and study microorganisms. These media are categorized by their composition, consistency, and functional roles, enabling researchers to investigate microbial physiology, behavior, and interactions.Types and Consistencies of Growth MediaGrowth media can be solid, liquid, or semisolid. Solid media, often agar-based, allow visible colony growth for isolation and enumeration.
1.1K
Microorganisms in Medicine and Therapeutics01:29

Microorganisms in Medicine and Therapeutics

845
Microorganisms play a fundamental role in vaccine development, gene therapy, and therapeutic production. Their biological properties are harnessed to advance medicine and public health. Beyond immunization, microorganisms contribute to gut health, antibiotic synthesis, and genetic disease treatment.Live Attenuated and Inactivated VaccinesLive attenuated vaccines, such as the measles, mumps, and rubella (MMR) vaccine, utilize weakened forms of pathogens to closely resemble natural infections.
845

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Farmed Escapees Threaten MHC Diversity in Wild Atlantic Salmon.

Evolutionary applications·2026
Same author

Whole-genome sequencing reveals a novel <i>Renibacterium salmoninarum</i> lineage and suggests geographic endemism combined with anthropogenic spread in the North-East Atlantic Area.

Applied and environmental microbiology·2026
Same author

Daily cheese intake positively affects serum osteocalcin levels, vitamin K status and bone turnover markers in elderly men and women.

BMJ nutrition, prevention & health·2026
Same author

Highly Pathogenic Avian Influenza A (H5N1) Caused Mass Death Among Black-Legged Kittiwakes (<i>Rissa tridactyla</i>) in Norway, 2023.

Transboundary and emerging diseases·2026
Same author

Cecal microbiota and Clostridium perfringens in broilers fed barley-based diets: Effects of enzyme supplementation and degree of grinding.

Poultry science·2026
Same author

First report of a parapoxvirus red deer infection in reindeer (Rangifer tarandus tarandus): clinical presentation and full-genome characterization.

Virology journal·2025

Related Experiment Video

Updated: Dec 24, 2025

The Cultivation, Growth, and Viability of Lactic Acid Bacteria: A Quality Control Perspective
04:40

The Cultivation, Growth, and Viability of Lactic Acid Bacteria: A Quality Control Perspective

Published on: June 16, 2022

9.1K

Engineering Lactococcus lactis for Increased Vitamin K2 Production.

Cathrine Arnason Bøe1, Helge Holo1,2

  • 1Laboratory of Microbial Gene Technology, Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, Ås, Norway.

Frontiers in Bioengineering and Biotechnology
|April 8, 2020
PubMed
Summary
This summary is machine-generated.

Enhancing vitamin K2 (menaquinone) production in Lactococcus lactis involves optimizing the menaquinone side chain synthesis. Overexpressing key genes like mvk and preA significantly boosts menaquinone levels in fermented milk.

Keywords:
Lactococcus lactisMK-3MK-8MK-9menaquinonemevalonate kinaseprenyl diphosphate synthasevitamin K2

More Related Videos

Novel Production Protocol for Small-scale Manufacture of Probiotic Fermented Foods
08:38

Novel Production Protocol for Small-scale Manufacture of Probiotic Fermented Foods

Published on: September 10, 2016

25.1K
Antimicrobial Peptides Produced by Selective Pressure Incorporation of Non-canonical Amino Acids
11:56

Antimicrobial Peptides Produced by Selective Pressure Incorporation of Non-canonical Amino Acids

Published on: May 4, 2018

12.9K

Related Experiment Videos

Last Updated: Dec 24, 2025

The Cultivation, Growth, and Viability of Lactic Acid Bacteria: A Quality Control Perspective
04:40

The Cultivation, Growth, and Viability of Lactic Acid Bacteria: A Quality Control Perspective

Published on: June 16, 2022

9.1K
Novel Production Protocol for Small-scale Manufacture of Probiotic Fermented Foods
08:38

Novel Production Protocol for Small-scale Manufacture of Probiotic Fermented Foods

Published on: September 10, 2016

25.1K
Antimicrobial Peptides Produced by Selective Pressure Incorporation of Non-canonical Amino Acids
11:56

Antimicrobial Peptides Produced by Selective Pressure Incorporation of Non-canonical Amino Acids

Published on: May 4, 2018

12.9K

Area of Science:

  • Microbiology
  • Biochemistry
  • Food Science

Background:

  • Cheese is a primary source of vitamin K2 (menaquinone) in Western diets.
  • Subclinical vitamin K2 deficiency is prevalent, necessitating foods with higher vitamin K2 content.
  • Lactococcus lactis is crucial for vitamin K2 production in fermented foods.

Purpose of the Study:

  • To identify and overcome bottlenecks in menaquinone biosynthesis in Lactococcus lactis.
  • To enhance vitamin K2 production through genetic manipulation of L. lactis.
  • To develop L. lactis strains for increased vitamin K2 content in fermented foods.

Main Methods:

  • Cloning and expression of key genes in the menaquinone pathway of L. lactis MG1363.
  • Overexpression of menaquinone biosynthesis genes, individually and in combination.
  • Analysis of menaquinone production and side chain length.
  • Application of engineered strains in milk fermentation.

Main Results:

  • The menaquinone polyprenyl side chain synthesis, not the naphthoate ring, limits menaquinone production.
  • Overexpression of menF and menA favored short-chain menaquinone (MK-3) production.
  • Overexpression of mvk and llmg_0196 (preA) enhanced long-chain menaquinone (MK-9) production.
  • Single overexpression of mvk, preA, menF, or menA at least doubled menaquinone content.
  • Combined overexpression of mvk, preA, and menA further increased menaquinone levels.
  • Engineered strains achieved a 3-fold increase in vitamin K2 content during milk fermentation.

Conclusions:

  • The polyprenyl side chain synthesis is a critical target for enhancing menaquinone production in L. lactis.
  • Specific gene overexpression strategies can significantly increase vitamin K2 content.
  • This research provides a basis for developing functional foods with elevated vitamin K2 levels.