Mass spectrometric investigations on lactate adduction to equine myoglobin.

This paper investigates whether lactate, a molecule produced during physical exertion, interacts directly with myoglobin, a protein in muscle tissue, using laser-based investigative techniques. The study found that there is presumably no direct interaction between the lactate and the myoglobin.

Research Methodology

• The researchers targeted their investigation on lactate’s direct effect on myoglobin. Myoglobin is a protein found in muscle cells and is responsible for transporting oxygen within these cells. Lactate is a chemical compound formed in the body through the process of anaerobic respiration and is often associated with muscle fatigue during strenuous physical activities.
• Two types of myoglobin were used for this study: equine oxymyoglobin and equine carboxymyoglobin, at a concentration of 0.15 millimolar.
• The myoglobins were incubated with sodium lactate (200mM) under two different conditions: at a cold temperature of 4 degrees Celsius, pH 5.6, in 50mM sodium citrate buffer to mimic meat storage conditions, and at body temperature (37 degrees Celsius), pH 7.4, in 50mM sodium phosphate buffer to mimic physiological conditions.
• Control variables involved myoglobin and an equivalent volume of deionized water used to introduce lactate.

Research Findings

• The team utilized a technique called Matrix Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry (MALDI-ToF MS) to observe any interactions between the lactate and myoglobin. This technique permits the identification and characterization of biological compounds like proteins and peptides.
• They analyzed the samples after incubation at different intervals up to 360 minutes at body temperature and up to 8 days at cold storage temperature. They were examining for peaks in the mass spectra which would symbolize lactate-myoglobin adducts—evidence of a chemical bond formation between lactate and myoglobin.
• No such “lactate-Mb adducts” were noted. Hence, the research suggests that there is no direct chemical interaction between lactate and both types of myoglobin under the conditions tested.