[01] Abdulhadi Sale Kumurya, Department of Medical Laboratory Science, Faculty of Allied Health Sciences, Bayero University, Kano, Nigeria.

Staphylococcus aureus has emerged as one of the most important human pathogens, and has over the past several decades, been a leading cause of hospital and community acquired infections. Methicillin-resistant strains of S. aureus (MRSA) were first recognized in the 1980’s as a major clinical and epidemiological problem. Hospitals are still facing this problem today. Preservation of strains in a microbiology laboratory is of great importance for quality control, teaching, and research. Freezing is a very common method of preservation and storage of microorganisms. Studies concentrate on the viability of the microorganisms after a certain storage period. Little attention is given to the influence of storage conditions on characteristics of the stored strains. This article describes methods, reagents, and equipment commonly utilized for the growth, maintenance, and characterization of S. aureus in the laboratory. It also explains the methods of identification of S. aureus as methicillin resistant strains, and generated a method for freezer stock of S. aureus for long-term storage. The Microbank Bacterial Preservation system (Pro-lab Diagnostics) is a well-known system for freezer storage of all kinds of microorganisms and is used in laboratories all over the world. Staphylococcus aureus is a Biosafety Level 2 (BSL-2) pathogen. Follow all appropriate guidelines and regulations for the use and handling of pathogenic microorganisms. No special precautions are necessary when working with MRSA.

Staphylococcus aureus, MRSA, Growth, Strain Selection, Freezer Stock

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