Karl, Michael and Holler, Eggehard (1998) Multiple polypeptides immunologically related to beta-poly(L-malate) hydrolase (polymalatase) in the plasmodium of the slime mold Physarum polycephalum. EUROPEAN JOURNAL OF BIOCHEMISTRY, 251 (1-2). pp. 405-412. ISSN 0014-2956
Full text not available from this repository.Abstract
Plasmodia of Physarum polycephalum contain large amounts of the cell-type-specific polyanion beta-poly(L-malate) and of a corresponding specific hydrolase (polymalatase), both expressed in the plasmodial form of the organism. We have partially purified polymalatase, the preparation consisting of several polypeptides, which could not be separated without destroying the hydrolase activity. Polypeptides of 68 kDa and 97 kDa were identified as polymalatases. Both were glycosylated, the 68-kDa form giving rise to a 54-kDa form when deglycosylated, and the 97-kDa form giving rise to an 88-kDa polypeptide that was indistinguishable from an 88-kDa inactive species also contained in the enzyme preparation. Antisera against each of these proteins were used to detect the intracellular distribution of the proteins. We found that the antisera crossreacted with the three proteins and, furthermore, with a multiplicity of polypeptides ubiquitously distributed over the plasmodium. Results of a two-dimensional non-denaturing in the first dimension and SDS-denaturing polyacrylamide,eel electrophoresis in the second dimension suggested that the proteins were derived from a 200-kDa 'precursor' protein by proteolytic fragmentation. Polymalatase activity could be generated from a high molecular-mass precursor. According to several pieces of evidence, the proteolytic nicking occurred within plasmodia. The fragments were sticky and gave rise to preferred sizes of nicked macromolecules. The observed multiplicity varied as a function of the age of the cultures. The cellular distribution and the intracellular pH value were not compatible with an in situ polymalatase activity and suggested other, presently unknown, function(s) such as in the transportation of beta-poly(L-malate) from the nucleus to the culture medium.
| Item Type: | Article |
|---|---|
| Uncontrolled Keywords: | DNA-POLYMERASE-ALPHA; POLYACRYLAMIDE GELS; PROTEINS; Physarum polycephalum; beta-poly(L-malate); polymalatase; fragmentation; immune cross-reactivity |
| Subjects: | 500 Science > 540 Chemistry & allied sciences 500 Science > 570 Life sciences |
| Divisions: | Biology, Preclinical Medicine > Institut für Biophysik und physikalische Biochemie > Alumni or Retired > Prof. Dr. Eggehard Holler |
| Depositing User: | Dr. Gernot Deinzer |
| Date Deposited: | 28 Feb 2023 10:36 |
| Last Modified: | 28 Feb 2023 10:36 |
| URI: | https://pred.uni-regensburg.de/id/eprint/50151 |
Actions (login required)
 |
View Item |
