Search PubMed⌕ Search

Biomedical subjects

M Krishnan

Publications and source records attributed to M Krishnan.

52 records · Page 3Linked to original sources
PubMed1986

An efficient and prolonged in vitro translational system from isolated cucumber etioplasts.

Etioplasts were isolated from dark grown cucumber cotyledons pretreated with kinetin and gibberellic acid. When incubated in a cofactor enriched medium these etioplasts incorporated [35S] methionine into a hot trichloroacetic acid-insoluble fraction; this incorporation was linear for 8 h of incubation and was inhibited by chloramphenicol but not by cycloheximide. Over the same time period, the etioplasts showed continued linear synthesis of the chlorophyll precursors protochlorophyllide, Mg-protoporphyrin and protoporphyrin IX. Analysis of products of in vitro protein synthesis by etioplasts and cotyledons showed the thylakoid membrane polypeptide profiles to be identical. Continued incorporation of [35S] methionine into the large subunit of ribulose bisphosphate carboxylase/oxygenase (RuBisCO) for 8 h has been confirmed further by immunoprecipitation with anti-spinach RuBisCO. This competent in vitro translation system should be useful for future studies of chloroplast protein synthesis and gene expression.

Amino Acids↗
PubMed1984

Radioisotopic evidence for the polypeptides associated with photosystem II.

Direct radioisotopic evidence for the polypeptides associated with oxygen evolution in a non-destructive approach by comparing the polypeptides of photosystem II (PS II) particles in etioplasts that lack O2 evolution with that of chloroplasts that exhibit high rates of oxygen evolution is reported. Polypeptide analysis by coomassie blue staining revealed that 32, 23 and 15 kDa proteins were absent in etioplast particles but developed in chloroplast PS II particles after illumination. However, a strikingly different picture was obtained when labelled polypeptides were analyzed from the fluorograph. While the new proteins identified by coomassie blue staining were also labelled, intensely labelled major polypeptides of molecular range 40, 41, 43 kD and minor polypeptides of molecular range 47, 48, 51 kD were observed in chloroplast PS II particles but not in etioplasts or etioplast particles; these labelled polypeptides were so prominent that they could be identified even in thylakoid membranes.

Chlorophyll↗
PubMedDate not supplied

A case of uremia-associated pleural effusion in a peritoneal dialysis patient.

The development of pleural effusions in ESRD patients is a relatively common occurrence. Uremia, currently a rare cause of effusion, can lead to the development of hemorrhagic pleural fluid collections in patients who are underdialyzed. Uremic pleural effusions should be considered when common etiologies of effusions such as volume overload, congestive heart failure (CHF), infection, and malignancy have been excluded. Uremia-associated serosal injury allows transudation of fluid into the pleural space, and defective platelet function contributes to the hemorrhagic nature of the effusion. Although uremic effusions may occur less frequently in peritoneal dialysis patients, we present a patient who developed this complication due to a peritoneal dialysis regimen that was inadequate by current Dialysis Outcomes Quality Initiative guidelines. The pleural effusion resolved with an intensified dialysis regimen in the absence of a change in the underlying volume status.

Adult↗