Related Experiment Video

Updated: Oct 1, 2026

Inducing a Site Specific Replication Blockage in E. coli Using a Fluorescent Repressor Operator System
11:19

Inducing a Site Specific Replication Blockage in E. coli Using a Fluorescent Repressor Operator System

Published on: August 21, 2016

The restriction-modification system in Streptomyces flavopersicus

D Lyutzkanova1, M Stoilova-Disheva, V Peltekova

  • 1Institute of Microbiology, Bulgarian Academy of Sciences, Sofia 1113, Bulgaria.

Folia Microbiologica
|August 15, 2001
PubMed

Insights

Streptomyces flavopersicus restricts DNA methylated by E. coli's dcm system. For cloning, use E. coli NM544, as S. flavopersicus does not process DNA from this strain, enabling successful bifunctional vector cloning.

Area of Science:

  • Microbiology
  • Molecular Biology
  • Genetics

Background:

  • Cloning bifunctional vectors in Streptomyces species requires understanding their restriction-modification systems.
  • Streptomyces flavopersicus possesses a restriction-modification system that impacts DNA cloning efficiency.

Purpose of the Study:

  • To define the restriction-modification system of Streptomyces flavopersicus.
  • To establish optimal conditions for cloning bifunctional vectors in S. flavopersicus.

Main Methods:

  • Plasmid DNA from E. coli strains with varying methylation states (dam/dcm) was isolated.
  • Isolated plasmid DNA was used to transform protoplasts of S. flavopersicus.
  • Restriction patterns of incoming DNA were analyzed to identify methylation-dependent inhibition.

Main Results:

  • Streptomyces flavopersicus was found to restrict DNA methylated by the E. coli dcm system.
  • DNA from E. coli strain NM544 (dam+ dcm) was not processed by S. flavopersicus, indicating successful cloning is possible with this strain.

Conclusions:

  • The dcm methylation system is responsible for DNA restriction in Streptomyces flavopersicus.
  • E. coli NM544 is the recommended intermediate host strain for cloning bifunctional vectors in S. flavopersicus due to its dcm methylation status.

More Related Videos

Visual and Microscopic Evaluation of Streptomyces Developmental Mutants08:42

Visual and Microscopic Evaluation of Streptomyces Developmental Mutants

Published on: September 12, 2018

A Fluorescence-based Method to Study Bacterial Gene Regulation in Infected Tissues07:10

A Fluorescence-based Method to Study Bacterial Gene Regulation in Infected Tissues

Published on: February 19, 2019

Related Concept Videos

Prokaryotic Transcriptional Activators and Repressors01:58

Prokaryotic Transcriptional Activators and Repressors

The organization of prokaryotic genes in their genome is notably different from that of eukaryotes. Prokaryotic genes are organized, such that the genes for proteins involved in the same biochemical process or function are located together in groups. This group of genes, along with their regulatory elements, are collectively known as an operon. The functional genes in an operon are transcribed together to give a single strand of mRNA known as polycistronic mRNA.
Transcription of prokaryotic...
Restriction Enzymes01:11

Restriction Enzymes

Restriction enzymes are bacterial enzymes used to cut DNA in a sequence-specific manner. To cleave DNA, they bind to specific palindromic sequences called restriction sites. Such palindromic DNA sequences or inverted repeats are commonly found in regions of functional significance, such as the origin of replication, gene operator sites, and regions containing transcription termination signals.
The host bacteria protect their own genomic DNA from these enzymes by methylating these sites. Some...
Prokaryotic Transcriptional Activators and Repressors01:58

Prokaryotic Transcriptional Activators and Repressors

The organization of prokaryotic genes in their genome is notably different from that of eukaryotes. Prokaryotic genes are organized, such that the genes for proteins involved in the same biochemical process or function are located together in groups. This group of genes, along with their regulatory elements, are collectively known as an operon. The functional genes in an operon are transcribed together to give a single strand of mRNA known as polycistronic mRNA.
Transcription of prokaryotic...
Repressible Operon: trp Operon01:21

Repressible Operon: trp Operon

The trp operon in Escherichia coli exemplifies a repressible operon. It regulates the synthesis of tryptophan through repressor-mediated transcriptional control and attenuation. This dual regulatory mechanism ensures tryptophan biosynthesis occurs only when needed, conserving cellular resources.Structure of the trp OperonThe trp operon consists of five structural genes (trpE, trpD, trpC, trpB, and trpA) that encode enzymes for tryptophan biosynthesis. These genes are transcribed as a single...
Transcriptional Regulation: Riboswitches01:23

Transcriptional Regulation: Riboswitches

Riboswitches are RNA elements that regulate gene expression by altering their secondary structures in response to specific effector molecules. These elements, located in the leader regions of certain mRNAs, act as transcriptional regulators by toggling between alternative conformations to control downstream gene expression. Riboswitch-mediated regulation is a precise mechanism for modulating biosynthetic pathways, as exemplified by the riboflavin biosynthesis pathway in Bacillus...
Stringent Response in E. coli01:23

Stringent Response in E. coli

Bacterial growth is closely tied to nutrient availability, with cells proliferating exponentially under favorable conditions and entering a stationary phase when resources become scarce. This transition is mediated by a regulatory mechanism known as the stringent response, which allows bacteria to adapt to nutrient deprivation by modulating gene expression and metabolic activity.During nutrient scarcity, intracellular amino acid levels decline. It results in the accumulation of uncharged tRNAs...