ACID HYDROLYSIS OF INTACT MYOGLOBIN
Francine Nicole M. Lim, Mikko Edison P. Maniego, Lea C. Maomay, Kyle Mendoza,
Meg Joen F. Misa, Sharra Jessamine Pasia

ABSTRACT
Myoglobin functions as an storage protein for oxygen. Hydrolysis is done primarily to obtain information about the protein. The myoglobin extracted was brownish red in color. The isolated protein was subjected to autoclaving for five hours at 15 psi. After autoclaving, the resultant solution was clear and colorless. The acid component (HCl) added prior to autoclaving was neutralized by the addition of a base, 1-molar NaOH. The neutralized acid hydrolysate was used for characterization tests and chromatography.

INTRODUCTION Proteins, from the Greek proteios, meaning first, are a class of organic compounds which are present in and vital to every living cell. In the form of enzymes, hormones, antibodies, and globulins, they catalyze, regulate, and protect the body chemistry. In the form of hemoglobin, myoglobin and various lipoproteins, they effect the transport of oxygen and other substances within an organism.(1) Myoglobin is an extremely compact heme protein found primarily in cardiac and red skeletal muscles. It functions in the storage of oxygen and facilitates the transport of oxygen to the mitochondria for oxidative phosphorylation. (2) Hydrolysis is performed to obtain information about the said protein. (3) It is a process in which the compound reacts with water leading to its decomposition. It takes place via Nucleophilic Acyl Substitution.
Nucleophilic Acyl Substitution involves the attack of nucleophiles to acid carbonyls of the compound. This reaction would yield substitution products.
EXPERIMENTAL
A. Sample/s used:
The sample used is the myoglobin protein isolated from the minced beef muscle. The sample was brownish red in color, with the presence off minute fibers. B. Procedure:
Five milliliters of 6 molar Hydrochloric Acid (HCl) was added to 0.5 grams of isolated myoglobin in a hard glass tube. The hard glass tube was labelled properly. The tube was stoppered with cotton and subjected to autoclaving for 5 hours at 15 psi. The appearance of the mixture was taken note of. Ten millilitres of water was added to the mixture. The mixture was transferred to a 250 ml beaker. The mixture was neutralized upon the drop by drop addition of 1 molar Sodium Hydroxide (NaOH).
RESULTS
The isolated myoglobin was brownish red in color with the presence of minute fibers. The brownish red coloration came from the chromoprotein, heme. After autoclaving, the resultant was a clear colorless solution.

REFERENCES:
From internet sources: 1. Proteins, Peptides and Amino Acids http://www2.chemistry.msu.edu/faculty/reusch/virttxtjml/proteins.htm#aacd5
Retrieved: 1/15/12

2. Myoglobin http://www.phattimes.com/myoglobin/chapter2.htm Retrieved: 1/17/12
From books: 3. Crisostomo, A., et al., (2010) Laboratory manual in General Biochemistry., Philippines: C & E Publishing House