OPTIMIZATION OF GRAM POSITIVE BACTERIA DNA EXTRACTION PROTOCOLS AND PURITY AND CONCENTRATION ANALYSIS BY GEL ELECTROPHORESIS

This work aims to optimize protocols for extraction of bacterial Deoxyribonucleic Acid (DNA) in order to develop more practical, fast and less costly methodologies, therefore bringing improvements to the development of research and applications in laboratory routine based on the difficulty of establishing an ideal method that can extract Gram-positive bacterial DNA with excellent quality. The material and the bacterial strain Staphylococcus aureus 15 were provided by the Leao Sampaio University Center, where tests for DNA extraction were also carried out. The tests used were Sodium Dodecyl Sulfate (SDS); salting-out ; PROMEGA’s Kit and CTAB / Phenol / Chloroform and were analyzed using agarose gel electrophoresis. The best results were obtained through the use of PROMEGA's commercial kit, salting-out without the use of Proteinase K and CTAB / Phenol / Chloroform, with salting-out having greater advantages in relation to other methods because it brings speed, low cost, good concentration of extracted material and not be toxic. The molecular tests for the extraction of Staphyloccocus aureus DNA were successful in general, when comparing issues such as low cost, extracted concentration, sharpness of the bands in electrophoresis and practicality of the performance. The best method for a small laboratory routine or for future research would be the salting-out without proteinase K, thus concluding that it is possible to obtain an excellent DNA extraction with less complexity and low cost methods. DOI: http://dx.doi.org/10.16891/2317-434X.v9.e2.a2021.pp1133-1140a