Now, Pete. Care to explain the string of character's after Salmonella?
It's the antigenic formula used to designate the specific strain.
See, Salmonella is complicated. It's a bit more complicated than most other pathogens with which I work. There are two species of Salmonella: S. enterica and S. bongori. We don't really care about the latter one much at all.
There are 6 subspecies within S. enterica: subsp. enterica, salamae, arizonae, diarizonae, houtenae, and indica.
Within each of these 6 subspecies, there are numerous serovars: strains which can be distinguished based on their antigenic properties. All told, there are upwards of 4400 unique serovars of Salmonella, many of which carry their own name. Salmonella Typhimurium is a well-known example. Typhimurium is a serovar of S. enterica susp enterica, so the full name is something like this: S. enterica subsp. enterica servoar Typhimurium.
The immune system has a variety of molecules it uses to recognize antigens. In this case, we care about antibodies. An antigen is generally a short polypeptide, about 8 - 20 amino acids long. Each antibody is "trained" to recognize and respond to one specific non-self antigen, in an attempt to eliminate threats to the body. Bacteria exhibit a wide variety of different kinds of antigens, and various strains have antigens with unique structures. The various unique antigens each interact with their own unique antibody. There are different categories of antigen based on their location and function within the bacterial cell. The two most common classes are O antigens, present on the surface of cells, and H antigens, which are present on the flagella of a bacterium.
Now that you have a little background, the string of characters represents a method of serotyping - that is, characterizing using antibodies - that we use to identify unique strains of Salmonella. We use purified antibodies of known types to look for bacteria which express the antigens specific to those antibodies. That is the full set of antigenic reactions that this strain of Salmonella exhibits, and is presented in a standard format.
The format is: Salmonella [O antigen group] [specific O antigens (rare reactions in brackets)]:[motile H antigens (called phase 1)]:[non-motile H antigens (phase 2)]
As I said previously, a Salmonella serovar will sometimes have a specific name, like the aforementioned Typhimurium. That name is shorthand for an antigenic formula. In the case of Typhimurium, that formula is B 1,4,5,12:i:1,2.
So, if you wanted to be a douchebag, you could write out the full proper name of S. typhimurium as: S. enterica subsp. enterica B 1,4,5,12:i:1,2. Instead, we say Salmonella Typhimurium because fuck that fucking noise.
However, not all serovars have a common name, and thus we refer to them by their full antigenic formula. This strain is O group I, with O antigens 4, 5, and 12. Antigen 5 is a rare reaction for this O group. The motility-associated flagellar antigens are group i, and it does not have any non-motility associated H antigens.
In normal speech, we refer to it as "four five twelve i minus."
I stopped eating them a little over a year ago, I think? I take your advice, although I occasionally eat lunch stuff from the hot bar at the Korean deli down the street.
Comments
See, Salmonella is complicated. It's a bit more complicated than most other pathogens with which I work. There are two species of Salmonella: S. enterica and S. bongori. We don't really care about the latter one much at all.
There are 6 subspecies within S. enterica: subsp. enterica, salamae, arizonae, diarizonae, houtenae, and indica.
Within each of these 6 subspecies, there are numerous serovars: strains which can be distinguished based on their antigenic properties. All told, there are upwards of 4400 unique serovars of Salmonella, many of which carry their own name. Salmonella Typhimurium is a well-known example. Typhimurium is a serovar of S. enterica susp enterica, so the full name is something like this: S. enterica subsp. enterica servoar Typhimurium.
The immune system has a variety of molecules it uses to recognize antigens. In this case, we care about antibodies. An antigen is generally a short polypeptide, about 8 - 20 amino acids long. Each antibody is "trained" to recognize and respond to one specific non-self antigen, in an attempt to eliminate threats to the body. Bacteria exhibit a wide variety of different kinds of antigens, and various strains have antigens with unique structures. The various unique antigens each interact with their own unique antibody. There are different categories of antigen based on their location and function within the bacterial cell. The two most common classes are O antigens, present on the surface of cells, and H antigens, which are present on the flagella of a bacterium.
Now that you have a little background, the string of characters represents a method of serotyping - that is, characterizing using antibodies - that we use to identify unique strains of Salmonella. We use purified antibodies of known types to look for bacteria which express the antigens specific to those antibodies. That is the full set of antigenic reactions that this strain of Salmonella exhibits, and is presented in a standard format.
The format is: Salmonella [O antigen group] [specific O antigens (rare reactions in brackets)]:[motile H antigens (called phase 1)]:[non-motile H antigens (phase 2)]
As I said previously, a Salmonella serovar will sometimes have a specific name, like the aforementioned Typhimurium. That name is shorthand for an antigenic formula. In the case of Typhimurium, that formula is B 1,4,5,12:i:1,2.
So, if you wanted to be a douchebag, you could write out the full proper name of S. typhimurium as: S. enterica subsp. enterica B 1,4,5,12:i:1,2. Instead, we say Salmonella Typhimurium because fuck that fucking noise.
However, not all serovars have a common name, and thus we refer to them by their full antigenic formula. This strain is O group I, with O antigens 4, 5, and 12. Antigen 5 is a rare reaction for this O group. The motility-associated flagellar antigens are group i, and it does not have any non-motility associated H antigens.
In normal speech, we refer to it as "four five twelve i minus."