Massilia (bacterium)

Culture of ''Massilia''

Isolation of Massilia sp. commonly occurs on Reasoner's 2A (R2A) agar. Colonies are often shades of white, yellow, or orange, but may be blue-purple if producing the compound violacein.

Phylogeny

Members of the genus Massilia have been re-classified into other genera as of 2023 using 16S rRNA-based phylogenetic trees. Originally, the Massilia genus existed within a polyphyletic group of the Oxalobacteriaceae, alongside other genera including Duganella, Pseudoduganella, Janthinobacterium, Telluria, and Rugamonas. In 2023, it was discovered that the type species of the genus, Telluria mixta, had nomenclatural priority over the name "Massilia", having been validly published first. Thus, all isolated Massilia species have been reclassified into the following genera: Duganella, Pseudoduganella, Janthinobacterium, Telluria, Rugamonas, or the novel genera Mokoshia and Zemynaea.

Habitats

Massilia sp. are environmental organisms that are commonly associated with plants. They have been isolated from the soil, flowers, seeds, and roots of many species of plants. They are generally psychrophilic or mesophilic, preferring cool to moderate temperatures, and they are generally either strict aerobes or microaerophiles. Massilia are proficient at surface colonization, including the seed coat, emerging radicles, roots, and even the hyphae of Pythium.

Massilia have been isolated from other, sometimes extreme, environments as well, including the Sahara Desert, freshwater, glaciers, rocks, and air samples. Manganese-oxidizing Massilia have been isolated. In rare cases, some Massilia sp. have caused infections in humans. However, doctors presume that these infections were likely opportunistic, as Massilia sp. are generally considered environmental organisms, rather than animal-associated.

Metabolism

Complex polymer degradation

Some Massilia sp. are able to degrade cellulose or chitin, two naturally occurring carbohydrate polymers, using cellulase and endochitinase enzymes, respectively. Many Massilia produce extracellular proteases, which can degrade proteins, producing carbon and nitrogen for the organism to consume, Massilia have also been reported to hydrolyse gelatin, casein, starch, DNA, tyrosine, and more. Massilia may play a crucial role in carbon cycling due to their broad range of degradative enzymes,

Massilia also have the potential to degrade many pollutants present in the environment. Massilia sp. WF1 was able to degrade the polycyclic aromatic hydrocarbon phenanthrene, each when alone and when in co-culture with the fungal species Phanerochaete chrysosporium.

Plant-growth-promoting traits

Some Massilia sp. are capable of phosphorus solubilization in the soil. Phosphorus solubilization allows plants to take in more phosphorus, potentially promoting plant growth. Analysis of Massilia genomes has identified genes for producing auxins, plant hormones, which can promote or alter plant growth. Their hydrolysis of extracellular compounds, such as proteins or DNA, can also release nutrients for the plant or other bacteria to utilize.

Antibiotic production is found in a few Massilia isolates, though many of these antibiotic compounds have not been identified. Massilia rhizosphaerae has antibacterial activity against the plant pathogen *Ralstonia solanacearum.*Massilia antibiotica has antibacterial activity against the pathogens Escherichia coli and Pseudomonas aeruginosa.

Quorum-regulated traits

Some Massilia sp. are known to produce violacein, a pigment also prouduced by Chromobacterium violaceum. This produces blue-purple pigmented colonies. Violacein production is regulated by quorum-sensing. a mechanism by which bacteria alter their gene expression in response to the population density.

References

References

1. "Massilia". [[LPSN]].
2. (2022). "Massilia soli sp. nov., isolated from soil". International Journal of Systematic and Evolutionary Microbiology.
3. (2021). "Massilia rhizosphaerae sp. nov., a rice-associated rhizobacterium with antibacterial activity against Ralstonia solanacearum". International Journal of Systematic and Evolutionary Microbiology.
4. (October 1998). "Massilia timonae gen. nov., sp. nov., isolated from blood of an immunocompromised patient with cerebellar lesions". Journal of Clinical Microbiology.
5. (2022-03-24). "Characterisation of Waterborne Psychrophilic Massilia Isolates with Violacein Production and Description of Massilia antarctica sp. nov.". Microorganisms.
6. (2022). "Duganella dendranthematis sp. nov. and Massilia forsythiae sp. nov., isolated from flowers". International Journal of Systematic and Evolutionary Microbiology.
7. Bowman, John P.. (2023). "Genome-wide and constrained ordination-based analyses of EC code data support reclassification of the species of Massilia La Scola et al. 2000 into Telluria Bowman et al. 1993, Mokoshia gen. nov. and Zemynaea gen. nov.". International Journal of Systematic and Evolutionary Microbiology.
8. (2021-10-22). "Seed-Transmitted Bacteria and Fungi Dominate Juvenile Plant Microbiomes". Frontiers in Microbiology.
9. (2012-07-11). "Ecology of Root Colonizing Massilia (Oxalobacteraceae)". PLOS ONE.
10. (2022-01-20). "Diversity and bioprospecting for industrial hydrolytic enzymes of microbial communities isolated from deserted areas of south-east Morocco". AIMS Microbiology.
11. (2019-08-08). "Draft Genome Sequence of Manganese-Oxidizing Bacterium Massilia sp. Strain Mn16-1_5, Isolated from Serpentine Soil in Taitung, Taiwan". Microbiology Resource Announcements.
12. (2022-08-02). "Massilia timonae bacteremia: An unusual pathogen of septic abortion". IDCases.
13. (2021-10-01). "Massilia cellulosiltytica sp. nov., a novel cellulose-degrading bacterium isolated from rhizosphere soil of rice (Oryza sativa L.) and its whole genome analysis". Antonie van Leeuwenhoek.
14. (2010-02-11). "Purification and characterization of two extracellular endochitinases from Massilia timonae". Carbohydrate Research.
15. (2017). "Massilia phosphatilytica sp. nov., a phosphate solubilizing bacteria isolated from a long-term fertilized soil". International Journal of Systematic and Evolutionary Microbiology.
16. (2021-03-23). "Genome insight and description of antibiotic producing Massilia antibiotica sp. nov., isolated from oil-contaminated soil". Scientific Reports.
17. (2021-08-10). "Soil indigenous microorganisms weaken the synergy of Massilia sp. WF1 and Phanerochaete chrysosporium in phenanthrene biodegradation". Science of the Total Environment.
18. (2014). "Auxins as one of the factors of plant growth improvement by plant growth promoting rhizobacteria". Polish Journal of Microbiology.
19. (2020-09-01). "Description of Massilia rubra sp. nov., Massilia aquatica sp. nov., Massilia mucilaginosa sp. nov., Massilia frigida sp. nov., and one Massilia genomospecies isolated from Antarctic streams, lakes and regoliths". Systematic and Applied Microbiology.
20. (2021-08-18). "Microbial synthesis of violacein pigment and its potential applications". Critical Reviews in Biotechnology.
21. (2004-03-31). "Genetic analysis of violacein biosynthesis by Chromobacterium violaceum". Genetics and Molecular Research.