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John N. Reeve Neil H. Mendelson 《Biochemical and biophysical research communications》1973,53(4):1325-1330
The addition of 250 μg/ml pronase to either cells or minicells of Bacillus subtilis does not interfere with growth, macromolecular synthesis or maintenance of cell integrity. Radioactive amino acids such as proline or isoleucine taken up by cells or minicells are bound to surface components which prevent their release by washing. Pronase treatment causes the release of a significant percentage of these bound amino acids. In cells and minicells exposed to pronase before the addition of labeled amino acids, initial binding capacities are greatly reduced. These data suggest a new approach to the investigation of amino acid binding components on the surface of Bacillus subtilis. 相似文献
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Miao Pan Thomas J. Santangelo Ľubomíra Čuboňová Zhuo Li Harlette Metangmo Jane Ladner Jerard Hurwitz John N. Reeve Zvi Kelman 《Extremophiles : life under extreme conditions》2013,17(3):453-461
Proliferating cell nuclear antigen (PCNA) monomers assemble to form a ring-shaped clamp complex that encircles duplex DNA. PCNA binding to other proteins tethers them to the DNA providing contacts and interactions for many other enzymes essential for DNA metabolic processes. Most eukarya and euryarchaea have only one PCNA homolog but Thermococcus kodakarensis uniquely has two, designated PCNA1 and PCNA2, encoded by TK0535 and TK0582, respectively. Here, we establish that both PCNA1 and PCNA2 form homotrimers that stimulate DNA synthesis by archaeal DNA polymerases B and D and ATP hydrolysis by the replication factor C complex. In exponentially growing cells, PCNA1 is abundant and present at an ~100-fold higher concentration than PCNA2 monomers. Deletion of TK0582 (PCNA2) had no detectable effects on viability or growth whereas repeated attempts to construct a T. kodakarensis strain with TK0535 (PCNA1) deleted were unsuccessful. The implications of these observations for PCNA1 function and the origin of the two PCNA-encoding genes in T. kodakarensis are discussed. 相似文献
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C A Mancuso G Odham G Westerdahl J N Reeve D C White 《Journal of lipid research》1985,26(9):1120-1125
The glycerol diether phospholipids of 25 monocultures of methanogenic bacteria were isolated and degraded with hydriodic acid. The resulting alkyl iodides were converted to acetate esters and alcohols which were examined using capillary gas-liquid chromatography. The presence of C20 phytanol was observed in accordance with previous studies. Soft fragmentation by chemical ionization mass spectrometry combined with selected ion monitoring enabled the detection, for the first time, of C15 and C25 isoprenologues as components of the diether phospholipids in several strains. 相似文献
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