Man 

 Dog 



Sheep 

 Horse 

 Pig 



THE INDIVIDUAL GROUPS OF PROTEINS 443 



Total Protein. Fibrinogen. Globulin. Albumin.A 



72'6 4'2 28-3 40-1 



60*3 6-0 22-6 31-7 1 by 



7 2 '9 4* 6 30'o 38'3 j Lewinsky. 



80-4 4-5 47-9 38-0 ! 



8o'5 6-5 29-8 44-2 



The ratio globulin to albumin in man is usually i : 1-15 but 1 : 1-39 to 2-13 has been 

 found. In starvation the globulin increases. 



Man Other Animals 

 (by Schmidt). (by Bunge and Abderhalden). 



K 2 O 0-387 to 0*40 0-225 to 0*270 



Na 2 O 4-290 4-251 to 4-442 



CaO 0-155 0-119 to 0-131 



MgO o-ioi 0-040 to 0-046 



Cl . 3-565 to 3-659 3-627 to 4-170 



P 2 O 5 0-052 to 0-085 



Serum. 



Blood plasma contains four coagulable proteins, fibrinogen, serum 

 globulin, pseudoglobulin and serum albumin ; also a nucleoprotein 

 in small quantities. With the exception of fibrinogen the same 

 proteins are contained in serum. Serum also contains the other 

 constituents of blood. 



Defibrinated blood contains the red and white corpuscles in addi- 

 tion. These are removed by centrifuging and serum probably more or 

 less pigmented by haemoglobin results. 



Serum, free from haemoglobin, is a faintly yellow fluid of sp. gr. 

 1030 and alkaline to litmus. 



A dilute solution of serum (i-io of water) acidified with a drop of 

 acetic acid coagulates on heating at 70-80, chiefly between 73-75 



It gives all the general reactions for proteins. 



The Coagulable Proteins. 



According to Haslam l the three coagulable proteins of serum have 

 the following properties by means of which they can be separated : 



\ precipitated by half- 

 Globulin, or euglobulm insoluble in water . ' 

 . ... ... . ^saturation with 



Pseudoglobulin soluble in water . . , 



J ammonium sulphate. 



Albumin soluble in water, precipitated by complete saturation 

 with ammonium sulphate. 



Globulin or Euglobulin. 



Preparation. 



(a) Globulin is prepared by dialysing serum ; the precipitate is redissolved 

 in dilute salt solution and again dialysed. This process is repeated several 

 times. 



(b) Globulin is precipitated from serum by acidifying it with acetic acid 

 and passing carbon dioxide through it. The precipitate is dissolved in dilute 

 salt solution and again thrown out, preferably by dialysis or by sodium 

 chloride. 



1 Biochem. J., 1913, vol. vii. 



