Related Experiment Video
Updated: Aug 5, 2026

Investigating Flagella-Driven Motility in Escherichia coli by Applying Three Established Techniques in a Series
Published on: May 10, 2020
Properties of mutants in galactose taxis and transport
Abstract:
beta-Methylgalactoside (mgl) permease mutants of Escherichia coli, which are defective in three genes, mglA, mglB, and mglC, were assayed for galactose taxis and galactose transport. The mglB product is the galactose-binding protein. Previous evidence, supported by our new findings, shows that the galactose-binding protein is the recognition component for galactose taxis as well as for galactose transport. Most mutants defective in mglB showed strong effects on both chemotaxis and transport; however, a couple showed effects chiefly on one process or the other, thus allowing a separation of chemotaxis and transport. The mglA and mglC products have not yet been identified, but they must be components of the galactose transport machinery since mutants defective in mglA or mglC, or both, showed strongly reduced transport. Although some of these mutants showed little chemotaxis, most gave close to wild-type chemotactic responses. Thus, transport is not required for galactose taxis. The bacteria detect changes in the fraction of binding protein associated with galactose, not changes in the rate of transport.
More Related Videos
05:28Demonstration of Heterologous Complexes formed by Golgi-Resident Type III Membrane Proteins using Split Luciferase Complementation Assay
Published on: September 10, 2020
12:29Generation of Null Mutants to Elucidate the Role of Bacterial Glycosyltransferases in Bacterial Motility
Published on: March 11, 2022
Related Concept Videos
Membrane Proteins
The Significance of Membrane Transport
Transporters facilitate either an active or passive movement of solutes. They can allow a single-molecule transport down its...
Overview of Secretory Vesicles
Various proteins regulate the aggregation of molecules inside the secretory vesicles. Chromogranins...
Glucose Transporters
Facilitated diffusion-glucose transporters (GLUTs) are encoded by the solute-linked carrier (SLC) family 2, subfamily A gene family, or SLC2A. The 14 GLUT protein members are distributed into three classes:
Transport Across the Golgi
Evolution of New Traits in Microbes