Physics
Scientific paper
Sep 2005
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2005e%26psl.237..311p&link_type=abstract
Earth and Planetary Science Letters, Volume 237, Issue 3-4, p. 311-325.
Physics
18
Scientific paper
Understanding the magnetic properties of magnetite crystals (Fe3O4) produced by magnetotactic bacteria (MTBs) is of fundamental interest in fields of geosciences, biomineralization, fine particle magnetism, and planetary sciences. The database of bulk magnetic measurements on MTBs is, however, still too sparse to allow for generalizations due to difficulties in obtaining bacteria cells in sufficient quantities from natural environments, and the fact that only a few cultivable strains are available. Here we report the first series of magnetic measurements on two air-dried samples containing solely MTBs (wild-type cocci and Magnetobacterium bavaricum), which were directly isolated from carbonaceous lake sediments. Systematic rock magnetic studies show that: 1) the magnetosomes in cells are dominated by single-domain (SD) magnetite; 2) the samples have delta ratios δFC / δZFC higher than 2; 3) the measured low-temperature remanence cycling curves as well as the first-order-reversal-curve (FORC) diagrams are significantly different to those measured on synthetic SD-magnetite samples; and 4) the Verwey transition temperature (Tv, ˜100 K) of MTB cells is distinctly lower than that from stoichiometric magnetite (Tv, 120 125 K). Our results provide new insights on the magnetic properties of bacterial magnetite and advance the use of magnetic proxies for decoding the paleomagnetic signals of sediments containing bacterial magnetite.
Davila Alfonso F.
Frederichs Thomas
Hanzlik Marianne
Liu Qingsong
Pan Yongxin
No associations
LandOfFree
Rock magnetic properties of uncultured magnetotactic bacteria does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Rock magnetic properties of uncultured magnetotactic bacteria, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Rock magnetic properties of uncultured magnetotactic bacteria will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1282389