Enzyme assays for bacterial identification

Bacterial identification of enzymes is a biochemical property such as the presence or absence of enzymes in the biochemical reaction of bacteria. These reactions can lead to changes in the pH of the reaction system or the production of chromogenic substances. Add appropriate acid-base indicators or developers. Can be reflected. Enzyme test: (1) Urease test: urease producing bacteria can decompose urea to produce ammonia to make the medium alkaline. The indicator is phenol red, positive for red and negative for orange. (2) Amylase test: The amylase producing bacteria can further degrade the starch, and the gram-free iodine solution does not develop color; otherwise, it is dark blue. Basic Information Specialist classification: Digestive examination classification: biochemical examination Applicable gender: whether men and women apply fasting: fasting Tips: Pay attention to normal eating habits and pay attention to personal hygiene. Normal value The type and proportion of the flora in the body are normal, and the human body is in a state of dynamic balance and health. Clinical significance Bacterial biochemical reactions and their judgment: Bacterial biochemical reactions mainly detect the biochemical properties of bacteria for the metabolism of various chemical substances (carbohydrates, amino acids and proteins, inorganic salts, etc.) and the presence or absence of enzymes. These reactions can cause changes in the pH of the reaction system or the production of chromogenic substances, which can be reflected by the addition of a suitable acid-base indicator or developer. Abnormal results: The pathogenicity of Staphylococcus aureus is mainly related to various invasive enzymes (such as plasma coagulase, hyaluronidase, phospholipase, catalase, thermonuclease) and various toxins (hemolytic toxin, leukotoxin, etc.) Related to, certain strains of enterotoxin can cause food poisoning, manifested as acute gastroenteritis. Among Streptococcus, Streptococcus pyogenes, Streptococcus agalactiae and Streptococcus pneumoniae are three important pathogens that can cause suppurative tonsillitis, acute pharyngitis, iatrogenic infections, rheumatic fever, and small kidneys. Ball nephritis and respiratory infections. Infections caused by Enterococcus are most common in urinary tract infections, most of which are intra-hospital infections, often associated with urinary tract manipulation and catheterization, followed by trauma and postoperative infections in the abdomen and pelvis. There are also infections caused by other bacteria. Need to check the crowd: a variety of acute gastroenteritis, suppurative tonsillitis, acute pharyngitis, respiratory infections, urinary tract infections, hospital infections and other symptoms of bacterial infection in patients with unknown bacteria. Precautions Forbidden before examination: Pay attention to normal eating habits and pay attention to personal hygiene. Requirements for inspection: Actively cooperate with the doctor. Inspection process Enzyme test (1) Urease test: urease producing bacteria can decompose urea to produce ammonia to make the medium alkaline. The indicator is phenol red, positive for red and negative for orange. (2) Amylase test: The amylase producing bacteria can further degrade the starch, and the gram-free iodine solution does not develop color; otherwise, it is dark blue. Not suitable for the crowd Inappropriate crowd: No. Adverse reactions and risks No related complications and hazards have been found.