Products for Classifying Bacteria

2-Naphthyl caprylate is a chromogenic substrate for carboxylesterase and lipase. 2-naphthol is released upon hydrolyzation. By simultaneous coupling with a diazonium salt, the corresponding azo-dye is formed.

Naphthols can also be detected by fluorescence analysis, and can be used in a colorimetric assay for the extracellular lipase of Pseudomonas fluorescent B52.

4-Methylumbelliferyl phosphate (MUP) is a sensitive fluorogenic substrate for fluorometric and UV-spectrophotometric assays of phosphatase.

Phosphotase activity has long been studied due to its importance in cellular function. Upon dephosphorylation, MUP yields fluorescent 4-methylumelliferone (4-MU). This reaction has been used to spot PCR amplified products in ELISA and to classify bacteria.

More specifically, MUP can act as an indicator of C. perfringens because of its ability to detect phosphatase which is a highly specific indicator of C. perfringens.

Used as a chromogenic substrate for N-Acetyl-β-D-galactosaminidase, yielding a blue precipitate. It is also used to detect Candida albicans.

X-α-D-Glucoside is a white to off-white microcrystalline powder that is used as a chromogenic substrate for α-D-glucosidase, which yields a blue precipitate. It is used for the detection of Staphylococcus aureus and species within Bacilli. It is also used in the isolation of Enterobacter sakazakii.

Basic fuchsin is a fluorescent dye composed of rosaniline, magenta II, pararosaniline and new fuschsine. Basic fuchsin staining is certified to use for the detection of acid-fast bacilli and is commonly used in the Ziehl Neelsen staining method.

This dye has also been shown to stain tubercle Bacillus and to compare E. coli and Aerobacter aerogenes.

Brilliant Green is a stain for differentiating E. coli from S. typhosa. It is also used in bacteriological media.

C-390 is an antibacterial agent which is used for selective isolation of Pseudomonas aeruginosa from other bacterial species.

3-Indoxyl-β-D-glucuronic acid is used in detection and enumeration of E. coli. This chromogenic substrate is used for β-D-glucuronidase, and yields a blue precipitate upon cleavage.

H-Ala-pNAHCl is a substrate for L-alanine aminopeptidase, which is an enzyme that is localized in bacterial cell walls responsible for the cleavage of L-alanine from various peptides. Significant L-alanine aminopeptidase activity is specific to gram-negative microbes. Therefore, H-Ala-pNAHCl can be used in support of evidence that an organism is gram-positive or gram-negative. It is split by L-alanine aminopeptide into L-alanine and 4-nitroanine. The latter compound causes bacterial suspensions to turn yellow.

H-Ala-AMCTFA (L-Alanine 7-amido-4-methylcoumarin, trifluoroacetate salt) is a fluorogenic substrate for aminopeptidase that yields a blue fluorescent solution. This substrate is useful in differentiating between gram-positive and gram-negative bacteria.

L-Arabinose is an arabinose isomer widely found in nature, while D-arabinose is less common. L-Arabinose is a constituent of many biopolymers that make up plant cell walls.

This monosaccharide is often used in cell culture media, serving as a bacterial carbon source, and can be used to distinguish between bacteria based on their fermentation abilities.

L-Arabinose, in the absence of glucose, induces transcription of the ara operon in E. coli that encodes L-arabinose catabolizing enzymes. It does this by binding to the AraC protein and activating the P_BAD promoter. The P_BAD promoter is used in plasmid vectors as a switch for protein expression that can be turned on by L-arabinose or turned off by addition of glucose.

L-Malic acid, disodium salt is a dicarboxylic acid used to differentiate microorganisms based on their varying metabolic properties. It is a source of CO₂ in the Calvin cycle and an intermediate of the citric acid cycle.