Nanobacterium sanguineum

From MicrobeWiki, the student-edited microbiology resource

A Microbial Biorealm page on the genus Nanobacterium sanguineum

Classification

Higher order taxa

cellular organisms; Bacteria; unclassified Bacteria; Nanobacterium

Species

NCBI: Taxonomy

Nanobacterium sanguineum

Description and significance

The genus Nanobacterium is said to contain a group of microbes that, like the name suggests, have dimensions considerably lower than that of regular bacteria, and perhaps even rival those of viruses. Since its discovery, nanobacteria have been the subject of consistent controversy; due to the significant size difference, some researchers have debated whether or not the so-called microorganisms are even alive. Only recently has the backlash subsided, with new studies being released that seem to confirm the existence of nanobacteria as a lifeform.

The first discernable species of nanobacteria was dubbed Nanobacterium sanguineum in 1998 by Finnish researchers E. Olavi Kajander and Nev Ciftcioglu; together they found evidence of self-replicating nanobacteria in the blood of humans and cows, along with the presence of 16S ribosomal RNA, evidence that the microbes were indeed alive. In addition, they discovered a unique characteristic among nanobacteria; they all seemed to produce a thick cell envelope of sorts consisting of either calcium compounds or apatite. Due to this property, nanobacteria was hypothesized to be the cause of calcification in certain parts of the body (i.e. kidney stones, plaques in various organs), and was thus given a second name, calcifying nanoparticles (CNP).

However, a couple years later, it was theorized that the particles discovered may not have actually been alive or self-replicating at all. According to a paper published in 2000, the replication witnessed by Kajander and Ciftcioglu may have been due to the properties of apatite itself, and the RNA present was likely a contaminant of another bacteria.

In 2004, a paper written by John C. Lieske et al. revealed evidence of particles similar to nanobacteria in various calcified arteries and arterial plaques. These particles not only self-replicated, but were also stained by a DNA probe, suggesting that they may contain nucleic acids, which in turn suggests that these nanoparticles may indeed be alive.

Since then, efforts in isolating nanobacteria from various places in the human body have been a moderate success; nanobacteria have been witnessed in kidney stones, the blood of humans, coronary plaques, and nanobacteria antigens have been detected in those with ovarian cancer and arthritis. As a result of the implications of nanobacteria having some sort of responsibility in causing these ailments, recent there has been an emphasis on the pathological properties of nanobacteria and the risks and diseases it may be an indirect cause of.

Genome structure

Due to the relatively controversial nature of nanobacteria, the genome of any of the species within the genus have yet to be sequenced. However, now that evidence has been seen of nanobacteria containing nucleic acids, attempts to extract the 16S ribosomal RNA of any of its species may be the first step to sequencing the genome.

Cell structure and metabolism

Not much is known about the cell structure of species within Nanobacterium. When viewed under a electron microscope, they appear to be cellwalled microbes that are either rod-shaped or spherical, and staining attempts have indicated that, if they are indeed bacteria, they appear to be Gram negative. Nanobacteria also have the unique ability to produce a "shell" of sorts around their bodies composed of apatite or a calcium compound. The function of the "envelope" has yet to be determined.

The metabolic pathways of nanobacteria still prove to be a mystery as well, since there has yet to be infallible proof of RNA or DNA present within nanobacteria. However, one NASA study has shown that in a microgravity environment, nanobacteria seem to grow several times faster, which could serve to be a potential health risk with astronauts.

Ecology/Pathology

While nanobacteria may potentially be present practically everywhere, most have been isolated from the human body. Specifically, most particles have been located in any areas where calcification has taken place, i.e. kidney stones and coronary plaques. This suggests that nanobacteria and their calcium-coated shells are the direct cause of the production of kidney stones and such plaques. Additionally, recent evidence implies that nanobacteria may also be correlated to inflammation in various parts of the body, including cardiac valves, blood vessels, ovarian cancers, and Alzheimer's disease.

There also appears to be a strong correlation between nanobacteria and HIV infection. According to a recent study done in South Africa, the amount of anti-nanobacteria antibody was seventeen times higher in those infected with HIV than in those with relatively normal health. Such studies have proven extremely beneficial in the fight against HIV prevention, opening a door to yet another method of attack on the epidemic.

Application to Biotechnology

While it is unclear whether or not nanobacteria may prove useful to the biotechnology industry, it has opened the doors to a potentially revolutionary method of disease and illness treatment. Nanobac Pharmaceuticals is a company that has come to prominence in this category; the pharmaceutical company, which assimilated Drs. Kajander and Ciftcioglu's Finnish company Nanobac OY, has made researching nanobacteria and developing treatment of nanobacteria-induced diseases its primary objectives. While the profitable aspects of the company has made some researchers question the legitimacy of their research, the treatments the company has developed seem to be effective. In a study of one of Nanobac's treatments, patients suffering from chronic pelvic pain syndrome (CPPS) and prostatic stones were treated with comET, a cocktail of various vitamins, amino acids, and antibiotics, for three months, and the results were significantly positive; prostate stones decreased or broke down altogether in 50% of the patients, and symptoms of CPPS were significantly lowered in all of the patients.

Current Research

As mentioned previously, much of the current intrigue of nanobacteria is its pathological properties, and indeed, recent research of nanobacteria confirm this interest. Studies such as the HIV study have proven to be helpful in battling such diseases and ailments.

In the HIV study in particular, researchers have suggested that the level of nanobacteria antigen present in a patient's blood may be used as a way to monitor HIV viral load in individuals. In Third World countries such as South Africa, such tests would be much more inexpensive than contemporary methods of HIV testing, and would thus be a significant boon to HIV prevention in the world.

In addition, nanobacteria has been recently hypothesized to have a hand in periodontal diseases, or diseases of the teeth and gums. The calcification of accumulated dental plaque is a principle cause of diseases such as gingivitis and periodontitis, where microorganisms become prime for infection. It was discovered that the process of calcification of plaques is strikingly similar to that of nanobacteria; not only are the nucleating properties of calcified dental plaque similar to that of nanobacteria, but the pH conditions that are required for calcification of plaque is are also similar to those necessary for calcification of nanobacteria. Additionally, while it may perhaps be coincidental, most periodontal diseases are treated with Tetracyclin, a relatively prominently used antibiotic which curiously seems to be one of the only antibiotics that are particularly effective against nanobacteria.

Research is also still being done to further bolster the existence of nanobacteria as something other than a crystalline growth. In November 2006 Nanobac Pharmaceuticals released the first live footage of nanobacteria under a high powered microscope. The video also seemingly proved the existence of nanobacteria as more than just an apatite shell; decalcifying agents were applied to both nanobacteria and inorganic calcium crystals, and while the inorganic crystals dissolved completely, the nanobacteria were simply released from its calcium shell, resulting in what looked to be debris within the solution. While this in no way confirms the existence of nanobacteria being alive, it is a significant step forward in studies of the controversial microbe.

References

[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.

Edited by Allen Park, student of Rachel Larsen