nucleoid


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nucleoid

 [noo´kle-oid]
1. resembling a nucleus.
2. a nucleus-like body sometimes seen in the center of an erythrocyte.
3. the central region of a bacterium, consisting of a dense irregularly shaped region containing DNA material without a surrounding nuclear membrane.
4. the genetic material (nucleic acid) of a virus, situated in the center of the virion.

nu·cle·oid

(nū'klē-oyd),
1. Synonym(s): nucleiform
2. A nuclear inclusion body.
3. Synonym(s): nucleus (2)
[nucleo- + G. eidos, resemblance]

nucleoid

/nu·cle·oid/ (noo´kle-oid)
1. resembling a nucleus.
2. a nucleus-like body sometimes seen in the center of an erythrocyte.
3. the genetic material (nucleic acid) of a virus situated in the center of the virion.
4. the nuclear region of a bacterium, which contains the chromosome but is not limited by a nuclear membrane.

nucleoid

(no͞o′klē-oid′, nyo͞o′-)
n.
The undefined region of genetic material inside a prokaryotic cell, consisting of aggregated DNA.

nucleoid

A condensed body within a bacterium that contains the prokaryote’s genome.

nu·cle·oid

(nū'klē-oyd)
1. Synonym(s): nucleiform.
2. A nuclear inclusion body.
3. Synonym(s): nucleus (2) .
[nucleo- + G. eidos, resemblance]

nucleoid

  1. the chromosomal region of a BACTERIUM. In ESCHERICHIA COLI it comprises mainly DNA with some PROTEINS (analagous to, but not HISTONES) and RNA. The structure is very compact and the DNA is folded into a series of loops, that are supercoiled (see SUPERCOILED DNA).
  2. the DNA mass in the CHLOROPLAST or MITOCHONDRION.
  3. the core of ribonucleic acid and protein in the virion of a RETROVIRUS.

nu·cle·oid

(nū'klē-oyd)
1. A nuclear inclusion body.
2. Synonym(s): nucleus (2) .
[nucleo- + G. eidos, resemblance]

nucleoid

1. resembling a nucleus.
2. a nucleus-like body sometimes seen in the center of an erythrocyte.
3. the genetic material (nucleic acid) of a rickettsia, chlamydia and some viruses, e.g. poxviruses, situated in the center of the microorganism.
References in periodicals archive ?
The nucleoid displaying fine DNA fibrils occupied the central zone of the cells.
The nucleoid in longitudinal sections displayed thick DNA fibrils (Fig.
They displayed intact outer membrane and cytoplasmic membrane enclosing a periplasmic space and centrally placed nucleoid containing fine DNA fibrils (Fig.
coli cells grown on normal medium showed the cell wall composed of outer and cytoplasm membranes enclosing a periplasmic space, the nucleoid containing fine DNA fibril and the cytoplasm containing numerous ribosomes.
The abundance of SiR in the plastid is likely to affect its association with the nucleoid and could have consequences for structure and function of the DNA/protein complex, since SiR was shown to compact DNA and inhibit DNA replication in vitro.
Since posttranslational modification of nucleoid proteins might be an in vivo regulatory strategy to modulate structure and function of the plastid protein/DNA complexes, the isoelectric point of SIR is currently being examined as a first step towards assessing potential changes in the phosphorylation state of SiR during development.
The product of the ferredoxin:sulfite reductase (SiR) gene is a bifunctional protein that functions as a DNA binding protein in chloroplast nucleoids and plays an integral part in the plant's sulfur assimilation pathway.
One nucleoid associated protein is DCP68, which was identified from Glycine max suspension cells was identified as ferredoxin:sulfite reductase.
Plastids are semiautonomous organelles that perform different functions depending on the cell type in which they reside: Their specific function is closely coordinated with the replication and expression of its DNA, which may be correlated to changes in nucleoid structure.
During organellar development, nucleoid morphology and protein composition vary suggesting that nucleoid structure plays a role in the regulation of replication and transcription of the chloroplast genome.
3:15 A cDNA CLONE OF DCP68, A MAJOR DNA-BINDING PROTEIN OF SOYBEAN CHLOROPLAST NUCLEOIDS
Plastid nucleoid structure and protein composition vary during the development of proplastids to chloroplasts, suggesting that genome packaging may play a crucial role in the regulation of replication, transcription, and recombination.