Related Experiment Video

Updated: Aug 29, 2026

Following in Real Time the Impact of Pneumococcal Virulence Factors in an Acute Mouse Pneumonia Model Using Bioluminescent Bacteria
11:32

Following in Real Time the Impact of Pneumococcal Virulence Factors in an Acute Mouse Pneumonia Model Using Bioluminescent Bacteria

Published on: February 23, 2014

The indirect pathogenicity of Stenotrophomonas maltophilia

Daisuke Kataoka1, Hiromitsu Fujiwara, Tomoko Kawakami

  • 1Department of Microbiology and Pathology, Faculty of Medicine, Tottori University, 86 Nishi-cho, Yonago 683-8503, Japan. dkataoka@grape.med.tottori-u.ac.jp

International Journal of Antimicrobial Agents
|December 9, 2003
PubMed

Insights

Stenotrophomonas maltophilia releases beta-lactamases that promote the growth of other bacteria, even with antibiotics. This highlights a critical gap in chemotherapy against this indirect pathogen.

Area of Science:

  • Microbiology
  • Antimicrobial Resistance
  • Pathogenesis

Background:

  • Stenotrophomonas maltophilia possesses inducible beta-lactamases (L1 and L2) capable of hydrolyzing most beta-lactam antimicrobials.
  • The indirect pathogenic potential of S. maltophilia in co-infections remains incompletely understood.

Purpose of the Study:

  • To investigate the indirect pathogenicity of S. maltophilia.
  • To determine if S. maltophilia promotes the growth of susceptible bacteria in mixed cultures under antibiotic pressure.

Main Methods:

  • Bacterial growth was assessed by counting colony-forming units (CFU).
  • Cultures included pure and mixed setups with S. maltophilia and beta-lactam-susceptible bacteria (Serratia marcescens, Pseudomonas aeruginosa).
  • Antibiotic agents imipenem and ceftazidime were supplemented to assess their efficacy in preventing growth.

Main Results:

  • Beta-lactamase leakage from S. maltophilia was observed.
  • This leakage facilitated the growth of Serratia marcescens and Pseudomonas aeruginosa.
  • Growth promotion occurred even when imipenem or ceftazidime was present.

Conclusions:

  • S. maltophilia exhibits indirect pathogenicity by enabling the survival and growth of other bacteria.
  • Beta-lactamase activity is a key mechanism for this indirect effect.
  • This finding reveals a significant limitation in current chemotherapy strategies against S. maltophilia infections.

More Related Videos

Visualization of Streptococcus pneumoniae within Cardiac Microlesions and Subsequent Cardiac Remodeling08:25

Visualization of Streptococcus pneumoniae within Cardiac Microlesions and Subsequent Cardiac Remodeling

Published on: April 7, 2015

Oral Transmission of Listeria monocytogenes in Mice via Ingestion of Contaminated Food08:38

Oral Transmission of Listeria monocytogenes in Mice via Ingestion of Contaminated Food

Published on: May 6, 2013

Related Concept Videos

Bacterial Phylum Planctomycetes01:26

Bacterial Phylum Planctomycetes

Planctomycetes are a group of morphologically distinct bacteria predominantly classified into two orders: Planctomycetales and Brocadiales. These gram-negative bacteria exhibit unique features, including division by budding and the presence of stalks or appendages. Their cells are often found in rosette arrangements, and they are notable for possessing an S-layer in their cell envelope, which is relatively uncommon among bacteria. Additionally, Planctomycetes frequently exhibit intracellular...
Determinants of Bacterial Pathogenicity and Virulence01:20

Determinants of Bacterial Pathogenicity and Virulence

Pathogenic bacteria employ a variety of strategies to establish infections, including the secretion of extracellular enzymes that act as potent virulence factors. These enzymes facilitate bacterial colonization of host tissues and help evade immune surveillance. By targeting structural components of host tissues and interfering with immune mechanisms, these enzymes play a pivotal role in disease progression.Extracellular Enzymes Facilitating Tissue Invasion: Several bacterial pathogens secrete...
Inhalation Anthrax01:25

Inhalation Anthrax

Anthrax is a zoonotic disease caused by Bacillus anthracis, a Gram-positive, spore-forming bacterium. It primarily affects herbivorous animals but can be transmitted to humans through skin contact, ingestion, or inhalation of spores.Cutaneous anthrax, the most common form, typically results from direct contact with bacterial spores through skin abrasions and is generally less severe. Gastrointestinal anthrax results from eating undercooked or contaminated meat. It affects the mouth, throat, or...
Transmission of Pathogens01:24

Transmission of Pathogens

Pathogens spread from their reservoirs to susceptible hosts through three main routes: contact transmission, vehicle transmission, and vector transmission. Each route involves distinct mechanisms of transfer.Contact TransmissionThis category includes direct contact, indirect contact, and droplet transmission:Direct contact involves immediate physical interaction between individuals—such as a handshake—which can spread pathogens like Streptococcus pyogenes, the bacterium responsible for...
Atypical Pneumonia01:14

Atypical Pneumonia

Atypical pneumonia, often caused by Mycoplasma pneumoniae, is a form of pulmonary infection that differs from the classical presentation of bacterial pneumonia in both its cause and clinical symptoms. Mycoplasma pneumoniae is a pleomorphic bacterium notable for its lack of a rigid cell wall. This structural characteristic imparts resistance to beta-lactam antibiotics and significantly influences the bacterium’s behavior within the human host.Other pathogens responsible for the disease include...
Colonisation of Pathogens01:25

Colonisation of Pathogens

Pathogen colonization of host tissues is a critical step in the development of infectious diseases. Various pathogenic microorganisms, including bacteria, fungi, viruses, and protozoa, have evolved complex strategies to attach to, invade, and persist within host environments. These mechanisms enable pathogens to establish infections, evade immune responses, and resist antimicrobial treatments.Attachment to Host CellsIn bacteria, colonization typically begins with adherence to host epithelial...