ISSN:
1432-203X
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract The growth of Distichlis spicata suspension cultures in LS medium without NaCl was inhibited 54% by 2 mM proline. In medium containing 260 mM NaCl, 10 mM proline inhibited growth by only 22%. The uptake and metabolism of 10 mM L-[1-13C] proline was followed by 13C NMR and ninhydrin analyses of suspensions cultured in the presence of 0 or 260 mM NaCl. Uptake of 85 to 92% of the exogenous proline occurred within 72 h in all media. In 10 mM proline and no NaCl, cellular proline reached a maximm of 51.5 μmoles/g FW compared to 1.9 μmoles/g FW in suspensions not grown on proline. In medium containing 260 mM NaCl and proline, cellular proline reached 59–65 μmoles/g FW compared to 30–40 μmoles/g FW in controls grown without proline. The 13C-label in the proline-C1 was either retained in proline or disappeared, presumably released as carbon dioxide, by catabolism through the TCA cycle. Since no metabolite of 13C-proline was detected by NMR, proline was considered to be the molecule which inhibited the suspension culture growth.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00269924
