Crystal habits and magnetic microstructures of magnetosomes in coccoid magnetotactic bacteria

Ulysses Lins, Martha McCartney, Marcos Farina, Brichard B. Frankel, P R Buseck

Research output: Contribution to journalArticle

9 Citations (Scopus)

Abstract

We report on the application of off-axis electron holography and high-resolution TEM to study the crystal habits of magnetosomes and magnetic microstructure in two coccoid morphotypes of magnetotactic bacteria collected from a brackish lagoon at Itaipu, Brazil. Itaipu-1, the larger coccoid organism, contains two separated chains of unusually large magnetosomes; the magnetosome crystals have roughly square projections, lengths up to 250 nm and are slightly elongated along [111] (width/length ratio of about 0.9). Itaipu-3 magnetosome crystals have lengths up to 120 nm, greater elongation along [111] (width/ length ∼0.6), and prominent corner facets. The results show that Itaipu-1 and Itaipu-3 magnetosome crystal habits are related, differing only in the relative sizes of their crystal facets. In both cases, the crystals are aligned with their [111] elongation axes parallel to the chain direction. In Itaipu-1, but not Itaipu-3, crystallographic positioning perpendicular to [111] of successive crystals in the magnetosome chain appears to be under biological control. Whereas the large magnetosomes in Itaipu-1 are metastable, single-magnetic domains, magnetosomes in Itaipu-3 are permanent, single-magnetic domains, as in most magnetotactic bacteria.

Original languageEnglish (US)
Pages (from-to)463-474
Number of pages12
JournalAnais da Academia Brasileira de Ciencias
Volume78
Issue number3
StatePublished - 2006

Fingerprint

Magnetosomes
Habits
Bacteria
Holography
Brazil
Electrons

Keywords

  • High-resolution transmission electron microscopy
  • Magnetite
  • Magnetotaxis

ASJC Scopus subject areas

  • General

Cite this

Crystal habits and magnetic microstructures of magnetosomes in coccoid magnetotactic bacteria. / Lins, Ulysses; McCartney, Martha; Farina, Marcos; Frankel, Brichard B.; Buseck, P R.

In: Anais da Academia Brasileira de Ciencias, Vol. 78, No. 3, 2006, p. 463-474.

Research output: Contribution to journalArticle

@article{626adf8ec90d4ee092022fc1af927124,
title = "Crystal habits and magnetic microstructures of magnetosomes in coccoid magnetotactic bacteria",
abstract = "We report on the application of off-axis electron holography and high-resolution TEM to study the crystal habits of magnetosomes and magnetic microstructure in two coccoid morphotypes of magnetotactic bacteria collected from a brackish lagoon at Itaipu, Brazil. Itaipu-1, the larger coccoid organism, contains two separated chains of unusually large magnetosomes; the magnetosome crystals have roughly square projections, lengths up to 250 nm and are slightly elongated along [111] (width/length ratio of about 0.9). Itaipu-3 magnetosome crystals have lengths up to 120 nm, greater elongation along [111] (width/ length ∼0.6), and prominent corner facets. The results show that Itaipu-1 and Itaipu-3 magnetosome crystal habits are related, differing only in the relative sizes of their crystal facets. In both cases, the crystals are aligned with their [111] elongation axes parallel to the chain direction. In Itaipu-1, but not Itaipu-3, crystallographic positioning perpendicular to [111] of successive crystals in the magnetosome chain appears to be under biological control. Whereas the large magnetosomes in Itaipu-1 are metastable, single-magnetic domains, magnetosomes in Itaipu-3 are permanent, single-magnetic domains, as in most magnetotactic bacteria.",
keywords = "High-resolution transmission electron microscopy, Magnetite, Magnetotaxis",
author = "Ulysses Lins and Martha McCartney and Marcos Farina and Frankel, {Brichard B.} and Buseck, {P R}",
year = "2006",
language = "English (US)",
volume = "78",
pages = "463--474",
journal = "Anais da Academia Brasileira de Ciencias",
issn = "0001-3765",
publisher = "Academia Brasileira de Ciencias",
number = "3",

}

TY - JOUR

T1 - Crystal habits and magnetic microstructures of magnetosomes in coccoid magnetotactic bacteria

AU - Lins, Ulysses

AU - McCartney, Martha

AU - Farina, Marcos

AU - Frankel, Brichard B.

AU - Buseck, P R

PY - 2006

Y1 - 2006

N2 - We report on the application of off-axis electron holography and high-resolution TEM to study the crystal habits of magnetosomes and magnetic microstructure in two coccoid morphotypes of magnetotactic bacteria collected from a brackish lagoon at Itaipu, Brazil. Itaipu-1, the larger coccoid organism, contains two separated chains of unusually large magnetosomes; the magnetosome crystals have roughly square projections, lengths up to 250 nm and are slightly elongated along [111] (width/length ratio of about 0.9). Itaipu-3 magnetosome crystals have lengths up to 120 nm, greater elongation along [111] (width/ length ∼0.6), and prominent corner facets. The results show that Itaipu-1 and Itaipu-3 magnetosome crystal habits are related, differing only in the relative sizes of their crystal facets. In both cases, the crystals are aligned with their [111] elongation axes parallel to the chain direction. In Itaipu-1, but not Itaipu-3, crystallographic positioning perpendicular to [111] of successive crystals in the magnetosome chain appears to be under biological control. Whereas the large magnetosomes in Itaipu-1 are metastable, single-magnetic domains, magnetosomes in Itaipu-3 are permanent, single-magnetic domains, as in most magnetotactic bacteria.

AB - We report on the application of off-axis electron holography and high-resolution TEM to study the crystal habits of magnetosomes and magnetic microstructure in two coccoid morphotypes of magnetotactic bacteria collected from a brackish lagoon at Itaipu, Brazil. Itaipu-1, the larger coccoid organism, contains two separated chains of unusually large magnetosomes; the magnetosome crystals have roughly square projections, lengths up to 250 nm and are slightly elongated along [111] (width/length ratio of about 0.9). Itaipu-3 magnetosome crystals have lengths up to 120 nm, greater elongation along [111] (width/ length ∼0.6), and prominent corner facets. The results show that Itaipu-1 and Itaipu-3 magnetosome crystal habits are related, differing only in the relative sizes of their crystal facets. In both cases, the crystals are aligned with their [111] elongation axes parallel to the chain direction. In Itaipu-1, but not Itaipu-3, crystallographic positioning perpendicular to [111] of successive crystals in the magnetosome chain appears to be under biological control. Whereas the large magnetosomes in Itaipu-1 are metastable, single-magnetic domains, magnetosomes in Itaipu-3 are permanent, single-magnetic domains, as in most magnetotactic bacteria.

KW - High-resolution transmission electron microscopy

KW - Magnetite

KW - Magnetotaxis

UR - http://www.scopus.com/inward/record.url?scp=33748556885&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=33748556885&partnerID=8YFLogxK

M3 - Article

C2 - 16936936

AN - SCOPUS:33748556885

VL - 78

SP - 463

EP - 474

JO - Anais da Academia Brasileira de Ciencias

JF - Anais da Academia Brasileira de Ciencias

SN - 0001-3765

IS - 3

ER -