Prochlorococcus marinus

From MicrobeWiki, the student-edited microbiology resource

A Microbial Biorealm page on the genus Prochlorococcus marinus

Classification

P. marinus Image used with permission of http://www.genoscope.cns.fr

Higher order taxa

Bacteria (Domain); Cyanobacteria (Phylum); No Class Listed; Prochlorales (Order); Prochlorococcaceae (Family); Prochlorococcus (Genus)

NCBI: Taxonomy

Species

Prochlorococcus marinus

NCBI: Complete genome here

Description and significance

Prochlorococcus marinus was fist discovered and classified by Sallie W. Chrisholm in 1988.

Prochlorococcus marinus is the dominate photosynthetic organism in the ocean. It accounts for up to 60% of the ocean’s chlorophyll in many regions such as the subtropical Pacific and is vastly numerous, often occurring at 10^5 cells/ml, abundant over the range of 40 °N to 40 °S The primary production and carbon sequestering capabilities in the open, oligotrophic, ocean are performed by these tinniest of cyanobacteria. P.marinus ranges in size from .6 to .eight um and have genomes of range l.6 to 2.6 Mbp. Most strains however, have genomes sized around 1.7 or 2.4 Mbp. Many experts understand such a condensed genome to be representative of the minimal genomic requirements for photosynthetic microbes.

P. marinus utilizes divinyl chlorophyll b and a2 as its light harvesting photochemicals. Its identification is still greatly in flux as many potential systems (subspecies, ecotypes, multiple gene sequence comparisons…) of classification have merit and support for varying taxonomy. The primary and predominate distinction between types of Phroclorococcus marinus is the ratio of their chl b to chl a2. Strains fall into 2 categories: High B/A isolates that have adapted to low iridescence light levels and low B/A isolates which flourish under high iridescences of light.


Genome structure

Describe the size and content of the genome. How many chromosomes? Circular or linear? Other interesting features? What is known about its sequence? Does it have any plasmids? Are they important to the organism's lifestyle?

Cell structure and metabolism

Describe any interesting features and/or cell structures; how it gains energy; what important molecules it produces.

P. marinus Strain SS120 Structure and Metabolism.

Ecology

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Pathology

How does this organism cause disease? Human, animal, plant hosts? Virulence factors, as well as patient symptoms.

Application to Biotechnology

Does this organism produce any useful compounds or enzymes? What are they and how are they used?

Current Research

Enter summaries of the most recent research here--at least three required

References

1. Chisholm, S. W. et al. A novel free-living prochlorophyte abundant in the oceanic euphotic zone. Nature 334, 340–343 (1988): [1]

[Sample reference] Takai, K., Sugai, A., Itoh, T., and Horikoshi, K. "Palaeococcus ferrophilus gen. nov., sp. nov., a barophilic, hyperthermophilic archaeon from a deep-sea hydrothermal vent chimney". International Journal of Systematic and Evolutionary Microbiology. 2000. Volume 50. p. 489-500.

Rocap, G et al. Genome divergence in two Prochlorococcus ecotypes reflects oceanic niche differentiation Nature 424: 1042-1047 [2]

Edited by Stephen Hubbard, student of Rachel Larsen