CHAPTER 9
Amino Acid and Protein Metabolism
II. FURTHER ASPECTS OF THE AMINO ACID AND
PROTEIN METABOLISM OF TISSUES IN CULTURE
J. A. L U C Y *
Strangeways Research Laboratory, Cambridge, England
I. Introduction
297
II. Nutritional Studies
298
A. Experimental procedures
298
B. "Non-essential" amino acids
299
G. "Essential" amino acids
300
D. Discussion
301
III. Utilization of Amino Acids
302
A. Introduction
302
B. Comparative utilization
303
IV. Protein Metabolism
305
A. Synthesis
305
B. Induction and repression
307
C. Turnover and catabolism
309
V . Conclusion
311
References
312
I. I N T R O D U C T I O N
It has been shown in Chapter 2 that Tissue Culture embraces a number
of different methods, each of which has advantages and disadvantages
for particular purposes. When it is proposed to use Tissue Culture
in the study of a specific problem, it is essential to choose the particular
method that is best suited to the investigation in hand. For example,
serially propagated cell lines may be the preferred technique if one is
interested in the amino-acid metabolism of rapidly growing tissues;
the metabolic characteristics of cell strains have been discussed in
the previous chapter by Eagle and Levintow. On the other hand,
if the investigator is concerned with, for example, the study of the
amino-acid and protein metabolism of differentiation, or the metabolic
interactions of different types of cells within one tissue, then other
methods are clearly more suitable. Furthermore, when a primary
•Member of the external staff of the Medical Research Council.