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

Enzymes02:34

Enzymes

95.0K
Inside living organisms, enzymes act as catalysts for many biochemical reactions involved in cellular metabolism. The role of enzymes is to reduce the activation energies of biochemical reactions by forming complexes with its substrates. The lowering of activation energies favor an increase in the rates of biochemical reactions.
Enzyme deficiencies can often translate into life-threatening diseases. For example, a genetic abnormality resulting in the deficiency of the enzyme G6PD...
95.0K
Enzyme Kinetics01:19

Enzyme Kinetics

104.2K
Enzymes speed up reactions by lowering the activation energy of the reactants. The speed at which the enzyme turns reactants into products is called the rate of reaction. Several factors impact the rate of reaction, including the number of available reactants. Enzyme kinetics is the study of how an enzyme changes the rate of a reaction.
Scientists typically study enzyme kinetics with a fixed amount of enzyme in the controlled environment of a test tube. When more reactant, or substrate, is...
104.2K
Design Example: Strain Gauge Bridge or Wheatstone Bridge01:15

Design Example: Strain Gauge Bridge or Wheatstone Bridge

1.0K
The utilization of strain gauges as transducers for converting mechanical strain into electrical signals is a common practice in various engineering applications. These strain gauges are frequently integrated into Wheatstone bridge circuits to accurately measure parameters such as force or pressure. Within this context, each element within the circuit exhibits a resistance that undergoes subtle variations when subjected to mechanical strain. The primary objective is to convert minuscule...
1.0K
Wheatstone Bridge01:29

Wheatstone Bridge

1.2K
An ohmmeter is a resistance-measuring device. It works by applying a voltage to a resistor of unknown resistance and measuring the current across the resistor. The resistance value is deduced using Ohm's law. Usually, the standard configuration of an ohmmeter comprises a voltmeter or an ammeter. However, such configurations are limited in accuracy because the meters alter the voltage applied to the resistor and the current that flows through it.
Thus, for accurate resistance measurements, a...
1.2K
Bridge rectifier01:24

Bridge rectifier

1.6K
The bridge rectifier is essential in electronics for efficiently converting alternating current (AC) to direct current (DC). Comprised of four diodes configured in a bridge layout, this rectifier effectively processes both the positive and negative halves of the AC waveform, making it superior to half-wave and full-wave center-tapped rectifiers in terms of voltage regulation and output stability.
Operationally, the bridge rectifier allows current flow through two of its diodes during each...
1.6K
What is a Mode?01:07

What is a Mode?

26.4K
The mode is one of the commonly used measures of a central tendency. It is defined as the most frequent value in a data set.
There can be more than one mode in a data set if multiple values have the same highest frequency. For instance, suppose that the Statistics exam scores of 20 students are: 50; 53; 59; 59; 63; 63; 72; 72; 72; 72; 72; 76; 78; 81; 83; 84; 84; 84; 90; 93. Here, the mode is 72, as it occurs most frequently, five times.
A data set with two modes is called bimodal. For example,...
26.4K

You might also read

Related Articles

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

Sort by
Same author

Generation of the Camptothecin Scaffold by a Flavin-Catalyzed Photooxidative Skeletal Reorganization.

Angewandte Chemie (International ed. in English)·2026
Same author

Emerging technologies for the discovery of biosynthetic genes in plants.

Natural product reports·2026
Same author

Tuning reductase activity in monoterpene indole alkaloid biosynthesis.

Proceedings of the National Academy of Sciences of the United States of America·2026
Same author

Chemoenzymatic Synthesis with Plant Oxidases and Metabolic Engineering Enable Rapid Access to Rare Gibberellins.

Journal of the American Chemical Society·2026
Same author

Voacangine/coronaridine hydroxylases catalyze C19-hydroxylation in iboga alkaloid synthesis.

Planta·2026
Same author

Biosynthesis of cinchona alkaloids.

Nature·2026

Related Experiment Video

Updated: Feb 8, 2026

High-throughput Screening of Carbohydrate-degrading Enzymes Using Novel Insoluble Chromogenic Substrate Assay Kits
06:51

High-throughput Screening of Carbohydrate-degrading Enzymes Using Novel Insoluble Chromogenic Substrate Assay Kits

Published on: September 20, 2016

13.7K

Sarpagan bridge enzyme has substrate-controlled cyclization and aromatization modes.

Thu-Thuy T Dang1, Jakob Franke1, Ines Soares Teto Carqueijeiro2

  • 1John Innes Centre, Department of Biological Chemistry, Norwich Research Park, Norwich, UK.

Nature Chemical Biology
|June 27, 2018
PubMed
Summary

Researchers discovered three homologous cytochrome P450 enzymes in plants that produce monoterpene indole alkaloids. These enzymes enable the creation of complex alkaloid structures like sarpagans and β-carbolines.

More Related Videos

Large Area Substrate-Based Nanofabrication of Controllable and Customizable Gold Nanoparticles Via Capped Dewetting
05:51

Large Area Substrate-Based Nanofabrication of Controllable and Customizable Gold Nanoparticles Via Capped Dewetting

Published on: February 26, 2019

6.1K
Fabrication and Visualization of Capillary Bridges in Slit Pore Geometry
11:20

Fabrication and Visualization of Capillary Bridges in Slit Pore Geometry

Published on: January 9, 2014

9.3K

Related Experiment Videos

Last Updated: Feb 8, 2026

High-throughput Screening of Carbohydrate-degrading Enzymes Using Novel Insoluble Chromogenic Substrate Assay Kits
06:51

High-throughput Screening of Carbohydrate-degrading Enzymes Using Novel Insoluble Chromogenic Substrate Assay Kits

Published on: September 20, 2016

13.7K
Large Area Substrate-Based Nanofabrication of Controllable and Customizable Gold Nanoparticles Via Capped Dewetting
05:51

Large Area Substrate-Based Nanofabrication of Controllable and Customizable Gold Nanoparticles Via Capped Dewetting

Published on: February 26, 2019

6.1K
Fabrication and Visualization of Capillary Bridges in Slit Pore Geometry
11:20

Fabrication and Visualization of Capillary Bridges in Slit Pore Geometry

Published on: January 9, 2014

9.3K

Area of Science:

  • Biochemistry
  • Plant Science
  • Metabolic Engineering

Background:

  • Alkaloid biosynthesis pathways often involve complex cyclization reactions to form polycyclic scaffolds.
  • Cytochrome P450 enzymes play crucial roles in catalyzing diverse oxidative reactions in secondary metabolism.

Purpose of the Study:

  • To identify and characterize cytochrome P450 enzymes involved in the biosynthesis of monoterpene indole alkaloids.
  • To investigate the enzymatic mechanisms underlying the formation of sarpagan and β-carboline alkaloid classes.

Main Methods:

  • Isolation and expression of three homologous cytochrome P450s from Rauwolfia serpentina, Gelsemium sempervirens, and Catharanthus roseus.
  • Substrate scope analysis and enzymatic assays to determine reaction products and mechanisms.

Main Results:

  • Discovery of three homologous cytochrome P450s catalyzing key cyclization steps in alkaloid biosynthesis.
  • Demonstration that these enzymes provide entry into both sarpagan and β-carboline alkaloid pathways.
  • Evidence for a common enzymatic mechanism accommodating distinct substrates to yield different alkaloid classes.

Conclusions:

  • Homologous cytochrome P450s are key regulators of alkaloid structural diversity.
  • Enzyme-substrate interactions dictate whether cyclization or aromatization occurs, leading to distinct alkaloid products.
  • This work provides insights into the evolution and engineering of alkaloid biosynthetic pathways.