1) Two ampicillin resistant bacteria often present in salad;
Aeromonas spp. Gram Negative, Bacillus Pseudomonas spp. Gram Negative, Bacillus Oxidase Positive Oxidase Positive Fermentative Oxidative
The results found in table 2, match the specification for Aeromonas spp being gram negative, a bacillus fermentative and oxidase positive. However to come up with a specific species further tests such as a Møeller decarboxylase and dihydrolase reactions to help narrow down the identification by the presence of absence of enzymes, but Aeromonas spp. are difficult to distinguish between due to a lack of differential biochemical characteristics (Abbott, Cheung, & Janda, 2003).
2) NA plate: (151x10⁴)/0.1= 15,100,000 bacteria per 10.021g of salad …show more content…
Normally during cell wall synthesis peptidoglycan precursors is transported across the cell membrane into the periplasm where it binds to cell wall acceptors. These precursors undergo excessive cross linking by tranpeptidase and D-alanyl carboxypeptidase to synthesise the cell wall. The presence of β-lactam rings competitively inhibits the enzymes by binding to their active site. Thus inhibiting cell wall synthesis which stops cell division and causes lysis due to fragility of cell wall and high osmotic pressures. Aeromonas spp. contain the genetic information that codes for the synthesis of Beta-Lactamase an enzyme which inactivates the β-lactam ring via hydrolysis causing a resistance to ampicillin (Li, Chan, & Chen, 2016). Therefore, Aeromonas spp. with this resistance no this organism can grow in the presence of
Aeromonas spp. Gram Negative, Bacillus Pseudomonas spp. Gram Negative, Bacillus Oxidase Positive Oxidase Positive Fermentative Oxidative
The results found in table 2, match the specification for Aeromonas spp being gram negative, a bacillus fermentative and oxidase positive. However to come up with a specific species further tests such as a Møeller decarboxylase and dihydrolase reactions to help narrow down the identification by the presence of absence of enzymes, but Aeromonas spp. are difficult to distinguish between due to a lack of differential biochemical characteristics (Abbott, Cheung, & Janda, 2003).
2) NA plate: (151x10⁴)/0.1= 15,100,000 bacteria per 10.021g of salad …show more content…
Normally during cell wall synthesis peptidoglycan precursors is transported across the cell membrane into the periplasm where it binds to cell wall acceptors. These precursors undergo excessive cross linking by tranpeptidase and D-alanyl carboxypeptidase to synthesise the cell wall. The presence of β-lactam rings competitively inhibits the enzymes by binding to their active site. Thus inhibiting cell wall synthesis which stops cell division and causes lysis due to fragility of cell wall and high osmotic pressures. Aeromonas spp. contain the genetic information that codes for the synthesis of Beta-Lactamase an enzyme which inactivates the β-lactam ring via hydrolysis causing a resistance to ampicillin (Li, Chan, & Chen, 2016). Therefore, Aeromonas spp. with this resistance no this organism can grow in the presence of