prokaryote

[prō′kar·ē‚ōt]

(cell and molecular biology)

A primitive nucleus, where the deoxyribonucleic acid-containing region lacks a limiting membrane.

Any cell containing such a nucleus, such as the bacteria and the blue-green algae.

The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Prokaryote

an organism that does not have a typical cell nucleus and chromosomal apparatus. Prokaryotes include bacteria, blue-green algae, rickettsiae, and mycoplasms.

In the organic world, according to the latest classification system, prokaryotes are classified as a kingdom (Prokariota) or a superkingdom that is comparable to the kingdom or super-kingdom of eukaryotes. In prokaryotes, the physical substrate associated with the transmission and realization of hereditary information consists of a strand of deoxyribonucleic acid (DNA). The DNA usually has a ringlike shape and is localized more or less in the central part of the organism, which is called the nucleoid; the nucleoid is not separated by a membrane from the cytoplasm. Unlike the DNA in eukaryotes, the DNA in prokaryotes is usually not bound to histones (it does not form nucleohistone) and the functioning of genes is regulated through metabolites. Also, prokaryotes do not have mitochondria and complexly organized flagella.

Prokaryotes play a very important role in the cycle of matter in the biosphere. Blue-green algae were probably the first autotrophic organisms to appear on earth in the course of the evolution of life.

REFERENCE

Peshkov, M. A. Tsitologiia bakterii. Moscow-Leningrad, 1955.

IU. I. POLIANSKII

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References in periodicals archive

Construction of the Prokaryotic Expression Plasmid pET2Sa(+)-PtCacyBP and Expression of the Recombinant Plasmid in Escherichia coli in Response to Salinity Challenges

Molecular cloning of the calcyclin-binding protein gene from the swimming crab Portunus trituberculatus and its roles in salinity stress adaptation

Construction of the prokaryotic expression vector and protein expression

Characterization of a Neutral Protease Gene of Bacillus subtilis Isolated from the Guts of Bombyx mori

Plasmid pET-24a (Novagen, Wisconsin, USA) was used as an expression vector in prokaryotic system.

Cloning, expression and purification of penicillin binding protein2a pbp2a from methicillin resistant staphylococcus aureus: a study on immunoreactivity in balb/c mouse

The five-kingdom system does include prokaryotic and eukaryotic "superkingdoms," and classifies Bacteria and Archaebacterta as subkingdoms (Margulis & Schwarz, 1998).

Merging kingdoms and domains

Prokaryotic inclusions have been reported widely in oysters from the East and Gulf coasts and in mussels from the East and West coasts (e.g., Yevich & Barszcz 1983, Gulka & Chang 1984, Couch 1985, Gauthier et al.

Distribution of parasites and pathologies in sentinel bivalves: NOAA status and trends "Mussel Watch" Program

In this research, we identified 18 prokaryotic phyla; the two most prevalent phyla were Firmicutes (42.81-55.29%) and Bacteroidetes (21.26-27.82%).

The Microbial Community in the Feces of Cape Oryx (Oryx gazella) as Determined by High-throughput Illumina Sequencing Technology

Seemann, "Prokka: rapid prokaryotic genome annotation," Bioinformatics, vol.

Comparative Genomics of the First and Complete Genome of "Actinobacillus porcitonsillarum" Supports the Novel Species Hypothesis

For prokaryotic gene expression study, the pET26-avimer plasmid DNA was transformed into E.

Novel Recombinant Traceable c-Met Antagonist-Avimer Antibody Mimetic Obtained by Bacterial Expression Analysis

The structures of other prokaryotic NADP-IDHs have been reported, in which IDHs bind to [NADP.sup.+] in a closed conformation similar to that of EcIDH with [NADP.sup.+], whereas IDH from the hyperthermophile Aeropyrum pernix (ApIDH) could bind to [NADP.sup.+] and isocitrate even though their active sites are open [13, 14].

Crystal Structures of the Putative Isocitrate Dehydrogenase from Sulfolobus tokodaii Strain 7 in the Apo and [NADP.sup.+]-Bound Forms

IANS Bengaluru A city-based geologist has discovered 2,000-million-year-old"prokaryotic"microfossils -- considered to be the earliest form of life -- from the Indian subcontinent in the Gwalior basin of the Bundelkhand region near Jhansi.

Earliest form of life in India dating 2,000 mn years discovered

We deposited sequences in GenBank and performed genome annotation by using the NCBI Prokaryotic Genome Annotation Pipeline (https://www.ncbi.nlm.

Carbapenemase VCC-1-Producing Vibrio cholerae in Coastal Waters of Germany