Nitrate reductase from the magnetotactic bacterium<i>Magnetospirillum magnetotacticum</i>MS-1: purification and sequence analyses
Bibliographic record
Abstract
We purified the nitrate reductase from the soluble fraction of Magnetospirillum magnetotacticum MS-1. The enzyme was composed of 86- and 17-kDa subunits and contained molybdenum, non-heme iron, and heme c. These properties are very similar to those of the periplasmic nitrate reductase found in Paracoccus pantotrophus. The M. magnetotacticum nap locus was clustered in seven open reading frames, napFDAGHBC. The phylogenetic analyses of NapA, NapB, and NapC suggested a close relationship between M. magnetotacticum nap genes and Escherichia coli nap genes, which is not consistent with the 16S rDNA data. This is the first finding that the alpha subclass of Proteobacteria possesses a napFDAGHBC-type nap gene cluster. The nap gene cluster had putative fumarate and nitrate reduction regulatory protein (Fnr) and NarL protein binding sites. Furthermore, we investigated the effect of molybdate deficiency in medium on the total iron content of the magnetosome fraction and discussed the physiological function of nitrate reductase in relation to the magnetite synthesis in M. magnetotacticum.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".