Biomaterial Database

Use of shake cultures in a semisolid thioglycolate medium for differentiating staphylococci from micrococci. 1972

J B Evans, and W E Kloos

The standard diagnostic test for differentiating staphylococci from micrococci is based on the ability of the former to produce acid anaerobically in a glucose-containing growth medium. This test has been modified to provide greater convenience, easier interpretation of results, and better correlation with deoxyribonucleic acid (DNA) base composition. In the modified test, shake cultures in Brewer's fluid thioglycolate medium with 0.3% agar added are observed for growth in the anaerobic zone of the tubes. This test was applied to 125 strains of staphylococci and micrococci, and all except two strains gave results that were consistent with other criteria. Of particular interest were eight strains of Micrococcus saprophyticus and three strains of M. lactis that have a DNA composition of 30 to 37% guanine plus cytosine (GC). All 11 of these cultures produced anaerobic growth and thus would be classified as staphylococci. Strains of M. lactis that have a high GC content in their DNA grew only aerobically. Some cultures of staphylococci produced characteristic band patterns of anaerobic growth and other cultures produced only a few anaerobic colonies from an inoculum of 10(6) to 10(7) cells. These observations suggest some interesting genetic and metabolic capabilities in such cultures.

UI	MeSH Term	Description	Entries
D008722	Methods	A series of steps taken in order to conduct research.	Techniques,Methodological Studies,Methodological Study,Procedures,Studies, Methodological,Study, Methodological,Method,Procedure,Technique
D008751	Methylene Blue	A compound consisting of dark green crystals or crystalline powder, having a bronze-like luster. Solutions in water or alcohol have a deep blue color. Methylene blue is used as a bacteriologic stain and as an indicator. It inhibits GUANYLATE CYCLASE, and has been used to treat cyanide poisoning and to lower levels of METHEMOGLOBIN.	Methylthionine Chloride,Swiss Blue,Basic Blue 9,Chromosmon,Methylene Blue N,Methylthioninium Chloride,Urolene Blue,Blue 9, Basic,Blue N, Methylene,Blue, Methylene,Blue, Swiss,Blue, Urolene
D008837	Micrococcus	A genus of gram-positive, spherical bacteria found in soils and fresh water, and frequently on the skin of man and other animals.
D003470	Culture Media	Any liquid or solid preparation made specifically for the growth, storage, or transport of microorganisms or other types of cells. The variety of media that exist allow for the culturing of specific microorganisms and cell types, such as differential media, selective media, test media, and defined media. Solid media consist of liquid media that have been solidified with an agent such as AGAR or GELATIN.	Media, Culture
D003596	Cytosine	A pyrimidine base that is a fundamental unit of nucleic acids.
D004269	DNA, Bacterial	Deoxyribonucleic acid that makes up the genetic material of bacteria.	Bacterial DNA
D005285	Fermentation	Anaerobic degradation of GLUCOSE or other organic nutrients to gain energy in the form of ATP. End products vary depending on organisms, substrates, and enzymatic pathways. Common fermentation products include ETHANOL and LACTIC ACID.	Fermentations
D005947	Glucose	A primary source of energy for living organisms. It is naturally occurring and is found in fruits and other parts of plants in its free state. It is used therapeutically in fluid and nutrient replacement.	Dextrose,Anhydrous Dextrose,D-Glucose,Glucose Monohydrate,Glucose, (DL)-Isomer,Glucose, (alpha-D)-Isomer,Glucose, (beta-D)-Isomer,D Glucose,Dextrose, Anhydrous,Monohydrate, Glucose
D006147	Guanine
D000332	Aerobiosis	Life or metabolic reactions occurring in an environment containing oxygen.	Aerobioses