426 BACTERIOLOGICAL CHEMISTRY 



electric field with the globulins, which have about the 

 same isoelectric point. 



As a result of analysis of serum proteins by the use 

 of Tiselius' apparatus for electrophoresis it is known 

 that albumin shows greatest mobility in an electric field 

 whilst normal globulin separates into three fractions, 

 a-, j3- and y-, which move progressively more slowly. 

 All these fractions contain cholesterol, phospholipoids 

 and carbohydrates (glucosamine and mannose), the a- 

 and j8-globulins being richest in all of them. The anti- 

 bodies formed as a result of the injection of polysaccharide- 

 containing antigens, such as the soluble specific substances 

 of the pneumococcus or the somatic 0-antigens, are 

 usually associated with the y-globulin. Tetanus and 

 diphtheria antitoxins are associated with a new com- 

 ponent, T, not present in normal serum. The T com- 

 ponent has a mobility of 2xl0~^ cm. per second per 

 volt per cm., which is midway between the mobilities of 

 j3- and y-globulins. The antitoxins to CI. ivelchii, CI. 

 sordelli and CI. cedeynations also have a T component. The 

 antitoxins of hsemolytic streptococci. Staphylococcus, 

 CI. botulinum, CI. histolyticum and CI. septicum contain 

 both T and y-globulins in varying proportions, althougl. 

 the amount of y-globulin is usually greater than in 

 normal serum. So far all antitoxins which have been 

 tested contain the T component. Diphtheria antitoxin 

 shows a progressive increase of j3-globulin as the course 

 of immunisation proceeds, the y-globulin increasing at 

 first but soon reaching a steady value. The toxin- 

 antitoxin floccules from y-globulin antitoxin contain 

 about twice as much nitrogen as do the floccules from 

 ^-globulin. The complexes can be expressed as having 

 the composition (TA4)n and (TAg),! respectively. y-Glo- 

 bulin antitoxin combines with toxin more rapidly than 

 does )8-globulin antitoxin, but the complex is less stable. 



2. Specific Methods. — The specific methods depend on 

 sepai'ating tlie anti])ody fiom tlio inactive part, of tlie 



