SDS-PAGE for identification of species belonging to the Mycobacterium fortuitum complex

Response surface modeling integrated microtiter plate assay for Mycobacterium fortuitum biofilm quantification

In this study, the effects of agitation, temperature, and pH on biofilm formation by Mycobacterium fortuitum were studied and quantified through response surface modeling. The microtiter plate assay was optimized to achieve conditions favoring maximum mycobacterial biofilm quantification. Optical density (OD) measurement using a crystal violet assay was performed to estimate the amount of biofilm formed. Response surface methodology (RSM) results revealed an R² value of 96.18%, exhibiting a maximum OD of 2.119 (λ_570 nm) at a temperature of 37 °C and pH 7.0, under a static environment. The conditions were experimentally validated. Statistically significant results showed that the maximum biofilm was produced 96 h after mycobacterial inoculation. Thus, the results provide a basis for using RSM as an efficient optimization method for M. fortuitum biofilm assays. This approach can also be incorporated into strategies for screening anti-biofilm compounds, synthetic chemicals, drugs, or inhibitors against pathogenic mycobacteria.

Method of extraction and proteome profiling of mycobacteria using liquid chromatography-high resolution mass spectrometry

Advances in massively parallel sequencing, of complete bacterial genomes, have led to many novel findings in the field of genomics. However, these data often lack correlation with expressed protein profiles. It has been demonstrated that even very closely related genomes, such as in mycobacteria, express drastically different phenotypes. These phenotypes often have major roles in pathogenicity. Therefore, it is just as important to have a method for examining the proteome of a bacterium as well as its genome. These studies are further complicated in mycobacteria due to the cell wall and mycolic acid. A comprehensive method for the identification and characterization of the whole mycobacterium protein profile is needed. In the present study, a simple, sensitive, and specific liquid chromatography tandem mass spectrometry method was developed for the extraction, purification and profiling the mycobacterial proteome in various species. During development, sonication and bead-beating cell lysis protocol was tested using 15% Acetonitrile and 6 M guanidine-HCl (GuHCl) as extraction solvent. Sonication lysis in 6 M GuHCl with glass beads was the preferred method for cell lysis. This method was developed using reverse phase liquid chromatography and a Q Exactive ™ Plus Orbitrap™ mass spectrometer for peptide and protein identification. Bottom-up liquid chromatography-mass spectrometry LC–MS analysis resulted in identification of greater than 2500 proteins.

Bacterial Whole Cell Protein Profiling: Methodology, Applications and Constraints

Background:

In the era of modern microbiology, several methods are available for identification and typing of bacteria, including whole genome sequencing. However, in microbiological laboratories or hospitals where genomic based molecular typing methods and/or trained manpower are unavailable, whole cell protein profiling using sodium dodecyl sulfate polyacrylamide gel electrophoresis might be a useful alternative/supplementary method for bacterial identification, strain typing and epidemiology. Whole cell protein profiling by SDS-PAGE is based on the principle that under standard growth conditions, a bacterial strain expresses the same set of proteins, the pattern of which can be used for bacterial identification.

Objective:

The objective of this review is to assess the current status of whole cell protein profiling by SDS-PAGE and its advantages and constraints for bacterial identification and typing.

Results and Conclusions:

Several earlier and recent studies prove the potential and utility of this technique as an adjunct or supplementary method for bacterial identification, strain typing and epidemiology. There is no denying the fact that utility of this technique as an adjunct or supplementary method for bacterial identification and typing has already been demonstrated and its practical applications need to be evaluated further.

Molecular epidemiology of mycobacteriosis in wildlife and pet animals

The ecology of mycobacteria is shifting in accordance with environmental change and new patterns of interaction between wildlife, humans, and nondomestic animals. Infection of vertebrate hosts throughout the world is greater now than ever and includes a growing prevalence in free ranging and captive wild animals. Molecular epidemiologic studies using standardized methods with high discriminatory power are useful for tracking individual cases and outbreaks, identifying reservoirs, and describing patterns of transmission and are used with increasing frequency to characterize disease wildlife. This review describes current features of mycobacteriosis in wildlife species based on traditional descriptive studies and recent molecular applications.