Clinical evaluation of advanced MALDI-TOF MS for carbapenemase subtyping in Gram-negative isolates.

Unlabelled: The spread of carbapenemase-producing Enterobacterales (CPE) is emerging as a significant clinical concern in tertiary hospitals and, in particular, long-term care facilities with deficiencies in infection control. This study aims to evaluate an advanced matrix-assisted laser desorption/ionization (A-MALDI) mass spectrometry method for the identification of carbapenemases and further discrimination of their subtypes in clinical isolates. The A-MALDI method was employed to detect CPE target proteins.

Improving mass accuracy in matrix-assisted laser desorption ionization time-of-flight mass spectrometry analysis of pathogenic proteins using 6xHIS-tagged internal calibration.

Rationale: Linear mode of matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOFMS) has been routinely used for bacterial identification in the clinic, depending on the pattern analysis of spectral libraries rather than accurate mass measurement of ribosomal proteins (10-15 kDa). However, a demand for more accurate mass analysis of pathogens (e.g.

Clinical Performance of the Osmotic Shock-MALDI MS Method to Detect Klebsiella pneumoniae Carbapenemase in Clinical Isolates.

The World Health Organization recently highlighted the serious worldwide problem of the emergence of antibiotic-resistant or antibiotic multidrug-resistant bacteria. Carbapenem-resistant Enterobacterales, including carbapenemase-producing Enterobacterales (CPE), are major antibiotic-resistant bacteria that can be identified by various methods, including antibiotic susceptibility testing, PCR, and immunologic assays. However, there is a need for a faster, more accurate, low-cost, and easy method to detect CPE strains.

Optimization of a lysis method to isolate periplasmic proteins from Gram-negative bacteria for clinical mass spectrometry.

Purpose: Clinical mass spectrometry requires a simple step process for sample preparation. This study aims to optimize the method for isolating periplasmic protein from Gram-negative bacteria and apply to clinical mass spectrometry.

Experimental Design: The Klebsiella pneumoniae carbapenemase (KPC)-producing E.