Related Experiment Video
Updated: Jun 13, 2026

In Vivo Monitoring of Transcriptional Activity During Metabolic Transition Using a Bioluminescent Reporter in Yeast
Published on: February 21, 2025
Maltose and maltodextrin utilization by Listeria monocytogenes depend on an inducible ABC transporter which is
Shubha Gopal1, Daniela Berg, Nicole Hagen
1Department of Studies in Microbiology, University of Mysore, Mysore, India. sguom@yahoo.com
Background:
In the environment as well as in the vertebrate intestine, Listeriae have access to complex carbohydrates like maltodextrins. Bacterial exploitation of such compounds requires specific uptake and utilization systems.
Methodology/Principal Findings:
We could show that Listeria monocytogenes and other Listeria species contain genes/gene products with high homology to the maltodextrin ABC transporter and utilization system of B. subtilis. Mutant construction and growth tests revealed that the L. monocytogenes gene cluster was required for the efficient utilization of maltodextrins as well as maltose. The gene for the ATP binding protein of the transporter was located distant from the cluster. Transcription analyses demonstrated that the system was induced by maltose/maltodextrins and repressed by glucose. Its induction was dependent on a LacI type transcriptional regulator. Repression by glucose was independent of the catabolite control protein CcpA, but was relieved in a mutant defective for Hpr kinase/phosphorylase.
Conclusions/Significance:
The data obtained show that in L. monocytogenes the uptake of maltodextrin and, in contrast to B. subtilis, also maltose is exclusively mediated by an ABC transporter. Furthermore, the results suggest that glucose repression of the uptake system possibly is by inducer exclusion, a mechanism not described so far in this organism.
Related Concept Videos
Inducible Operons: lac Operon
ABC Transporters: Importer
In bacteria, based on the number of transmembrane helices and the chemical nature of their substrates, the ABC importers can be divided into three types:
Operons
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:
Glucose Absorption Into the Small Intestine
Carbohydrate Absorption
After being swallowed, the partially digested carbohydrates mix with gastric secretions in the stomach. However, the acidic environment...

