Related Experiment Video

Updated: Sep 29, 2026

Biosensor for Detection of Antibiotic Resistant Staphylococcus Bacteria
14:04

Biosensor for Detection of Antibiotic Resistant Staphylococcus Bacteria

Published on: May 8, 2013

Antibiotic resistance and plasmids of some human nasal isolates of Staphylococcus aureus

A A Salamah1

  • 1Botany and Microbiology Department, College of Science, King Saud University, Riyadh, Saudi Arabia.

Microbiologica
|April 1, 1992
PubMed

Insights

Staphylococcus aureus isolates show high resistance to penicillin and ampicillin but remain susceptible to vancomycin. Plasmids carrying aminoglycoside and tetracycline resistance were identified in the isolates.

Area of Science:

  • Microbiology
  • Infectious Diseases
  • Antimicrobial Resistance

Background:

  • Staphylococcus aureus is a significant human pathogen.
  • Understanding antimicrobial resistance patterns is crucial for effective treatment.

Purpose of the Study:

  • To determine the antimicrobial susceptibility profile of Staphylococcus aureus isolates.
  • To identify genetic elements associated with resistance.

Main Methods:

  • Antimicrobial susceptibility testing was performed on Staphylococcus aureus isolates.
  • Plasmid analysis was conducted to identify resistance genes.

Main Results:

  • All isolates were susceptible to vancomycin.
  • Over 90% susceptibility was observed for rifampicin, ampiclox, methicillin, erythromycin, and clindamycin.
  • High resistance rates were found for penicillin (91%), ampicillin (93.2%), and carbenicillin (70.4%).
  • Twelve plasmids were identified, with 35 Mdal and 11 Mdal plasmids conferring resistance to aminoglycosides and tetracyclines, respectively.

Conclusions:

  • Staphylococcus aureus isolates exhibit significant resistance to beta-lactamase-sensitive penicillins.
  • Vancomycin remains an effective treatment option against these isolates.
  • Specific plasmids are associated with aminoglycoside and tetracycline resistance.

More Related Videos

Deferred Growth Inhibition Assay to Quantify the Effect of Bacteria-derived Antimicrobials on Competition07:42

Deferred Growth Inhibition Assay to Quantify the Effect of Bacteria-derived Antimicrobials on Competition

Published on: September 3, 2016

Methodology for the Study of Horizontal Gene Transfer in Staphylococcus aureus10:39

Methodology for the Study of Horizontal Gene Transfer in Staphylococcus aureus

Published on: March 10, 2017

Related Concept Videos

Antibiotic Selection01:45

Antibiotic Selection

Researchers use antibiotic resistance genes to identify bacteria that possess a plasmid containing their gene of interest. Antibiotic resistance naturally occurs when a spontaneous DNA mutation creates changes in bacterial genes that eliminate antibiotic activity. Bacteria can share these new resistance genes with their offspring and other bacteria. The overuse and misuse of antibiotics have created a public health crisis, as resistant and multi-resistant bacteria continue to develop.Antibiotic...
Plasmids01:28

Plasmids

Plasmids are extrachromosomal DNA molecules found in bacteria, archaea, and some eukaryotic microbes like yeast. These small, circular DNA structures typically contain fewer than 30 genes, although some may exist linearly. Plasmids vary in their number within a cell, known as copy number. Single-copy plasmids are present in one copy per cell and multi-copy plasmids are present in multiple copies, reaching over 100 copies per cell.Plasmids usually replicate independently of the chromosomal DNA...
Development of Antibiotic Resistance01:30

Development of Antibiotic Resistance

Antibiotic resistance is a major public health concern that arises when bacteria evolve mechanisms to withstand the effects of antibiotic treatments. This resistance can be intrinsic, acquired through genetic mutations, or transferred between bacteria via horizontal gene transfer. The development of antibiotic resistance poses significant challenges in treating bacterial infections and necessitates ongoing research to develop new therapeutic strategies.Intrinsic resistance occurs when bacterial...
Staphylococcal Skin Infections01:29

Staphylococcal Skin Infections

Staphylococcus aureus is a Gram-positive coccus that resides harmlessly on the skin and mucous membranes of healthy individuals. When the skin barrier is breached, it can shift from a commensal to an opportunistic pathogen. This transition is facilitated by surface adhesins, such as clumping factor B and S. aureus surface protein G (SasG), which bind to structural proteins, including loricrin and cytokeratin, in the damaged epidermis. Protein A, another key factor, binds the Fc region of...
Mechanism of Antibiotic Resistance in MRSA01:25

Mechanism of Antibiotic Resistance in MRSA

Antibiotic resistance in bacteria arises when microorganisms evolve the ability to withstand drugs designed to kill them or inhibit their growth, rendering once-effective treatments useless. This phenomenon, driven by genetic change and selection under antibiotic exposure, poses a profound threat to modern medicine. Mechanisms include drug-inactivating enzymes (e.g., β-lactamases), efflux pumps that eject antibiotics, mutations altering antibiotic targets, decreased drug uptake, and acquisition...
Clinical Significance of Antibiotic Resistance01:25

Clinical Significance of Antibiotic Resistance

Methicillin-resistant Staphylococcus aureus (MRSA) presents a critical public health threat, arising from its capacity to resist β-lactam antibiotics due to acquisition of the mecA gene within the staphylococcal cassette chromosome mec (SCCmec). This gene encodes penicillin-binding protein 2a (PBP2a), which impairs binding efficacy of methicillin and other β-lactams. MRSA has evolved into distinct clonal lineages impacting humans and animals alike, reinforcing its significance within the One...