Cell wall response of bacteria Serratia marcescens LII61 – lipase and protease enzymes producer – in gram staining

This study was aimed to reveal cell wall response of Serratia marcescens LII61 to Gram staining and its lipase and protease activities. Microscopic characters were obtained through the Gram staining procedure performed on variations in the age of bacterial cultures (16, 18, 24, 48, and 72 hours) which were grown on Luria Bertani Broth medium. Lipase activity assay was carried out using a spectrophotometer, with lipolytic selective media and observed every 4 hours for 24 hours. Protease activity was carried out using spotted method on proteolytic selective media and observed at 48 hours incubation time. The results of this study on Gram staining showed that S. marcescens LII61 has a Gram variable character, which was indicated by the change in color of the cell wall resulting from gram staining at the observed age of the culture. The highest lipase activity was produced at 16 hours after incubation (29.39 U/mL) and protease activity was indicated by hydrolysis index at 48 hours i.e 1.2. The cell wall response of the S. marcescens LII61 is an interesting matter to discuss because so far the bacterium Serratia marcescens is known as bacil Gram negative. The presence of gram variable properties shown in the results of this study can be attributed to the ability of bacterial cell wall to adapt in unsuitable nutrient condition, pH, temperature and electrolyte content in the environment.