A nitroplast is an

organelle In cell biology, an organelle is a specialized subunit, usually within a cell (biology), cell, that has a specific function. The name ''organelle'' comes from the idea that these structures are parts of cells, as Organ (anatomy), organs are to th ...

found in certain species of

algae Algae ( , ; : alga ) is an informal term for any organisms of a large and diverse group of photosynthesis, photosynthetic organisms that are not plants, and includes species from multiple distinct clades. Such organisms range from unicellular ...

, particularly in the marine algae ''

Braarudosphaera bigelowii ''Braarudosphaera bigelowii'' is a coastal coccolithophore in the fossil record going back 100 million years to the Late Cretaceous. Coccolithophore The Family (biology), family Braarudosphaeraceae consist of single-celled coastal phytopla ...

''. It plays a crucial role in

nitrogen fixation Nitrogen fixation is a chemical process by which molecular dinitrogen () is converted into ammonia (). It occurs both biologically and abiological nitrogen fixation, abiologically in chemical industry, chemical industries. Biological nitrogen ...

, a process previously thought to be exclusive to

bacteria Bacteria (; : bacterium) are ubiquitous, mostly free-living organisms often consisting of one Cell (biology), biological cell. They constitute a large domain (biology), domain of Prokaryote, prokaryotic microorganisms. Typically a few micr ...

and

archaea Archaea ( ) is a Domain (biology), domain of organisms. Traditionally, Archaea only included its Prokaryote, prokaryotic members, but this has since been found to be paraphyletic, as eukaryotes are known to have evolved from archaea. Even thou ...

. The discovery of nitroplasts has significant implications for both cellular biology and

agricultural science Agricultural science (or agriscience for short) is a broad multidisciplinary field of biology that encompasses the parts of exact, natural, economic and social sciences that are used in the practice and understanding of agriculture. Professio ...

Discovery

In 1998, Jonathan Zehr, an ocean ecologist at the

University of California, Santa Cruz The University of California, Santa Cruz (UC Santa Cruz or UCSC) is a public university, public Land-grant university, land-grant research university in Santa Cruz, California, United States. It is one of the ten campuses in the University of C ...

, and his colleagues found an unknown DNA sequence that appeared to be for an unknown nitrogen-fixing

cyanobacterium Cyanobacteria ( ) are a group of autotrophic gram-negative bacteria that can obtain biological energy via oxygenic photosynthesis. The name "cyanobacteria" () refers to their bluish green (cyan) color, which forms the basis of cyanobacteria' ...

in the

Pacific Ocean The Pacific Ocean is the largest and deepest of Earth's five Borders of the oceans, oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean, or, depending on the definition, to Antarctica in the south, and is ...

, which they called

UCYN-A ''Candidatus'' Atelocyanobacterium thalassa, also referred to as UCYN-A, is a nitrogen-fixing species of cyanobacteria commonly found in measurable quantities throughout the world's oceans and some seas. Members of ''A. thalassa'' are spheroid ...

(unicellular cyanobacterial group A). At the same time, Kyoko Hagino, a paleontologist at Kochi University, was working to culture the host organism, ''B. bigelowii''. The existence of nitroplasts was first proposed by researchers studying the interaction between ''B. bigelowii'' and UCYN-A in 2012. Initially, it was hypothesized that UCYN-A facilitated nitrogen fixation, providing compounds like

ammonia Ammonia is an inorganic chemical compound of nitrogen and hydrogen with the chemical formula, formula . A Binary compounds of hydrogen, stable binary hydride and the simplest pnictogen hydride, ammonia is a colourless gas with a distinctive pu ...

to the algae. However, subsequent studies led by Jonathan Zehr reported that UCYN-A were organelles.

Structure and function

Nitroplasts exhibit typical organelle characteristics, meeting two key criteria: they are inherited during

cell division Cell division is the process by which a parent cell (biology), cell divides into two daughter cells. Cell division usually occurs as part of a larger cell cycle in which the cell grows and replicates its chromosome(s) before dividing. In eukar ...

and rely on

protein Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residue (biochemistry), residues. Proteins perform a vast array of functions within organisms, including Enzyme catalysis, catalysing metab ...

s provided by the host cell. Through

imaging Imaging is the representation or reproduction of an object's form; especially a visual representation (i.e., the formation of an image). Imaging technology is the application of materials and methods to create, preserve, or duplicate images. ...

studies, researchers observed that nitroplasts divide along with the host cell, ensuring their passage to daughter cells.

Implications

The discovery of nitroplasts challenges previous notions about the exclusivity of nitrogen fixation to

prokaryotic A prokaryote (; less commonly spelled procaryote) is a single-celled organism whose cell lacks a nucleus and other membrane-bound organelles. The word ''prokaryote'' comes from the Ancient Greek (), meaning 'before', and (), meaning 'nut' ...

organisms. Understanding the structure and function of nitroplasts opens up possibilities for

genetic engineering Genetic engineering, also called genetic modification or genetic manipulation, is the modification and manipulation of an organism's genes using technology. It is a set of Genetic engineering techniques, technologies used to change the genet ...

in plants. By incorporating genes responsible for nitroplast function, researchers aim to develop crops capable of fixing their own nitrogen, potentially reducing the need for nitrogen-based fertilizers and mitigating environmental damage.

References

External links

* {{organelles Algal anatomy Organelles

Discovery

Structure and function

Implications

See also

References

Further reading

External links