Conserved mass peaks of bacteria at the genus level

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) has been validated to be useful in identifying many microbial species to the species level. However, the approach relies on the existence of different mass peaks between different microbial species. Such differences manifest as differences in mass peak distribution in mass spectra of microbes that could be … More Conserved mass peaks of bacteria at the genus level

Theoretical ribosomal protein mass fingerprint database

Ribosomal proteins constitute the large and small subunit of the ribosome. Given the highly conserved nature of ribosomes, ribosomal proteins are expected to be similarly conserved. However, theoretical calculations of the molecular mass of ribosomal proteins of different species revealed the existence of distinct molecular mass fingerprint of ribosomal proteins from individual species. Such ribosomal … More Theoretical ribosomal protein mass fingerprint database

High accuracy timing mechanisms in time-of-flight mass spectrometers enable high mass resolution detection

High accuracy timing in time-of-flight mass spectrometers facilitate the accurate detection of time of arrival of different molecular ions, which when compared to a calibration chart of protein standards with known molecular weight, enables the calculation of mass/charge ratio of high mass resolution. Specifically, accuracy of the timing mechanism at the millisecond timescale provides a … More High accuracy timing mechanisms in time-of-flight mass spectrometers enable high mass resolution detection

Existence of ribosomal protein mass fingerprint of different bacterial, archaeal and eukaryotic species

Ribosomes are known to be highly conserved due to the importance of protein synthesis to cellular maintenance. Thus, constituent ribosomal proteins should theoretically be highly conserved, which implied a conserved amino acid sequence and molecular mass. However, unique molecular mass fingerprint of ribosomal proteins of individual species in the three domains of life was detected. … More Existence of ribosomal protein mass fingerprint of different bacterial, archaeal and eukaryotic species

Conserved mass peaks in mass spectra of bacterial species

Conserved mass peaks were found in mass spectra of individual bacterial species that highlighted a deep biological basis in the use of mass spectrometry for identifying bacteria. Specifically, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) could profile biomolecules (mostly proteins) from bacterial cells that result in a mass spectrum useful for identification purposes. While … More Conserved mass peaks in mass spectra of bacterial species

Long flight tube in time-of-flight mass spectrometer enables better separation of different analyte ions

Molecular ions literally fly through the flight tube of the time-of-flight mass spectrometer where at the end of the travel, they are detected as an electrical charge on the detector. The duration of flight was measured and is a key parameter for calculation of the mass/charge ratio of the molecular ion based on a calibration … More Long flight tube in time-of-flight mass spectrometer enables better separation of different analyte ions

Transfer of laser energy from matrix coating helps prevent fragmentation of molecules

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) ionizes molecules without inducing fragmentation, thereby allowing molecular ion to be detected, which helps data interpretation of mass spectrum. The mechanisms underlying the ability of the mass spectrometry technique to ionize molecules without inducing fragmentation lies in the use of special matrix compounds that help transfer laser … More Transfer of laser energy from matrix coating helps prevent fragmentation of molecules

Is there a theoretical mass limit to MALDI-TOF mass spectrometry?

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) uses a laser to ionize molecules from a matrix coated sample surface, accelerate them along a vacuum tube through the application of an electric field, and obtained a mass/charge ratio of the molecular ion by timing the flight of the ion. Given that time-of-flight of the molecular … More Is there a theoretical mass limit to MALDI-TOF mass spectrometry?

Need for proteome molecular mass library to aid peak identification in MALDI-TOF MS microbial identification

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) generates microorganism-specific mass spectrum which has been shown to be useful in microbial identification via the mass spectrum fingerprinting approach. Specifically, the mass spectrum of an unknown microorganism is compared against those catalogued in a reference database of known microbes to aid in positive identification of microbe. … More Need for proteome molecular mass library to aid peak identification in MALDI-TOF MS microbial identification

Protein identification is the key challenge in proteomics

Proteomics seek to uncover the ensemble of proteins within a cell or the cell surface. However, whether assisted by mass spectrometry or Western Blot, the key challenge in proteomics remain the identification of proteins. Protein identification remains laborious and time expensive even in the case of mass spectrometry-based proteomics where the challenge lies in the … More Protein identification is the key challenge in proteomics