''Arthrobacter alkaliphilus'' is a

Gram-positive In bacteriology, gram-positive bacteria are bacteria that give a positive result in the Gram stain test, which is traditionally used to quickly classify bacteria into two broad categories according to their type of cell wall. Gram-positive bac ...

and non-

spore In biology, a spore is a unit of sexual or asexual reproduction that may be adapted for dispersal and for survival, often for extended periods of time, in unfavourable conditions. Spores form part of the life cycles of many plants, algae, ...

-forming bacterium species from the genus of ''

Arthrobacter ''Arthrobacter'' (from the Greek, "jointed small stick”) is a genus of bacteria that is commonly found in soil. All species in this genus are Gram-positive obligate aerobes that are rods during exponential growth and cocci in their stationary ...

'' which has been isolated from filtrations from a

volcanic rock Volcanic rock (often shortened to volcanics in scientific contexts) is a rock formed from lava erupted from a volcano. In other words, it differs from other igneous rock by being of volcanic origin. Like all rock types, the concept of volcan ...

in Niigata in Japan.

Cell Morphology and Features

''Arthrobacter alkaliphilus'' is a non-motile, Gram-positive bacteria that demonstrates a rod-

coccus A coccus (plural cocci) is any bacterium or archaeon that has a spherical, ovoid, or generally round shape. Bacteria are categorized based on their shapes into three classes: cocci (spherical-shaped), bacillus (rod-shaped) and spiral ( of w ...

growth cycle. This was first observed upon culture of bacteria in Genus Arthrobacter where a young culture demonstrated an irregular rod shape which was replaced in older cultures by a coccoid form. When those older cultures were placed in a new media they again produced irregular rod shapes. It is this characteristic that makes Arthrobacter bacteria unique and hard to identify. In a culture of an Arthrobacter alkaliphilus colony scientists observed a round, convex, and glossy appearance with entire margins and a light yellow color. After 2–7 days the culture shows mostly coccoid

cell Cell most often refers to: * Cell (biology), the functional basic unit of life Cell may also refer to: Locations * Monastic cell, a small room, hut, or cave in which a religious recluse lives, alternatively the small precursor of a monastery w ...

s that are 0.6-1.0 micrometers in diameter. In most Arthrobacter bacteria the

fatty acids In chemistry, particularly in biochemistry, a fatty acid is a carboxylic acid with an aliphatic chain, which is either saturated or unsaturated. Most naturally occurring fatty acids have an unbranched chain of an even number of carbon atoms, f ...

found are primarily iso- and anteiso-branched which refers to a branch on the antepenultimate

carbon atom Carbon () is a chemical element with the symbol C and atomic number 6. It is nonmetallic and tetravalent—its atom making four electrons available to form covalent chemical bonds. It belongs to group 14 of the periodic table. Carbon makes up o ...

of a saturated fatty acid chain. Initial testing of bacteria found in volcanic rock showed that the major fatty acid was anteiso-C15 : 0 and the major amino acid present in the

cell wall A cell wall is a structural layer surrounding some types of cells, just outside the cell membrane. It can be tough, flexible, and sometimes rigid. It provides the cell with both structural support and protection, and also acts as a filtering mec ...

peptidoglycan was l-lysine a common amino acid used in the structure of many living organisms. Biochemical characteristics were assessed by Linxian Ding, Taketo Hirose, and Akira Yokota showing results for alkaline and a number of enzymes including; acid phosphatase, catalase, esterase lipase C8, leucine arylamidase, valine arylamidase, typsin, naphthol-AS-BI-phosphohydrolase, alpha- and beta-glucuronidase, alpha-glucosidase, alpha-mannosidase, pyrazinamidase, pyrrolidonyl arylamidase, and urease.

Phylogeny and genome evolution

This bacteria belongs to Phylum

Actinomycetota The ''Actinomycetota'' (or ''Actinobacteria'') are a phylum of all gram-positive bacteria. They can be terrestrial or aquatic. They are of great economic importance to humans because agriculture and forests depend on their contributions to soi ...

, Class

Actinomycetia The Actinomycetia are a class of bacteria. Taxonomy The currently accepted taxonomy is based on the List of Prokaryotic names with Standing in Nomenclature (LPSN) and National Center for Biotechnology Information (NCBI). * Acidothermales Sen e ...

, Order

Micrococcaceae The family ''Micrococcaceae'' includes bacterial genera of Gram positive cocci that inhabit the air and skin, such as '' Micrococcus luteus''. Genera The family ''Micrococcaceae'' comprises the following genera: * '' Acaricomes'' Pukall ''et a ...

, Family

, and Genus

. Shown below is the

genome In the fields of molecular biology and genetics, a genome is all the genetic information of an organism. It consists of nucleotide sequences of DNA (or RNA in RNA viruses). The nuclear genome includes protein-coding genes and non-coding ...

evolution for ''Arthrobacter alkaliphilus''. Also shown is the 1457 bp sequence length and corresponding GC content which is 60 mol%. PHYLO SUS

1 tggctcagga tgaacgctgg cggcgtgctt aacacatgca agtcgaacga tgaagcctag 61 cttgctgggt ggattaggtg gcgaacgggt gagtaacacg tgagtaacct gcccttgact 121 ctgggataag cctgggaaac tgggtctaat accggatatg actgctccgc gcatgcggtg 181 gtggtggaaa gcttttgcgg ttttggatgg actcgcggcc tatcagcttg ttggtggggt 241 aatggcctac caaggcgacg acgggtagcc ggcctgagag ggtgaccggc cacactggga 301 ctgagacacg gcccagactc ctacgggagg cagcagtggg gaatattgca caatgggcgc 361 aagcctgatg cagcgacgcc gcgtgaggga tgacggcctt cgggttgtaa acctctttca 421 gtagggaaga agctttcggg tgacggtacc tgcagaagaa gcgccggcta actacgtgcc 481 agcagccgcg gtaatacgta gggcgcaagc gttatccgga attattgggc gtaaagagct 541 cgtaggcggt ttgtcgcgtc tgctgtgaaa gaccggggct caactccggt tctgcagtgg 601 gtacgggcag actagagtga tgtaggggag actggaattc ctggtgtagc ggtgaaatgc 661 gcagatatca ggaggaacac cgatggcgaa ggcaggtctc tgggcattaa ctgacgctga 721 ggagcgaaag catggggagc gaacaggatt agataccctg gtagtccatg ccgtaaacgt 781 tgggcactag gtgtggggga cattccacgt tttccgcgcc gtagctaacg cattaagtgc 841 cccgcctggg gagtacggcc gcaaggctaa aactcaaagg aattgacggg ggcccgcaca 901 agcggcggag catgcggatt aattcgatgc aacgcgaaga accttaccaa ggcttgacat 961 ggactagtaa gacgcagaaa tgtgttcccc tctttgaggc tggtttacag gtggtgcatg 1021 gttgtcgtca gctcgtgtcg tgagatgttg ggttaagtcc cgcaacgagc gcaaccctcg 1081 ttctatgttg ccagcggttc ggccggggac tcataggaga ctgccggggt caactcggag 1141 gaaggtgggg acgacgtcaa atcatcatgc cccttatgtc ttgggcttca cgcatgctac 1201 aatggccggt acaaagggtt gcgatactgt gaggtggagc taatcccaaa aagccggtct 1261 cagttcggat tggggtctgc aactcgaccc catgaagtcg gagtcgctag taatcgcaga 1321 tcagcaacgc tgcggtgaat acgttcccgg gccttgtaca caccgcccgt caagtcacga 1381 aagttggtaa cacccgaagc cggtggccta acccttgtgg agggagccgt cgaaggtggg 1441 accggcgatt gggacta

Metabolic details

The BacDive is a worldwide database that uses cultured data demonstrating ''Arthrobacter’s''

metabolism Metabolism (, from el, μεταβολή ''metabolē'', "change") is the set of life-sustaining chemical reactions in organisms. The three main functions of metabolism are: the conversion of the energy in food to energy available to run c ...

and

physiology Physiology (; ) is the scientific study of functions and mechanisms in a living system. As a sub-discipline of biology, physiology focuses on how organisms, organ systems, individual organs, cells, and biomolecules carry out the chemic ...

. ''Arthrobacter'' is a gram-positive bacterium and it requires oxygen to fully utilize its carbon diet. It can consume glucose, lactose, maltose, mannitol, and ribose. Arthrobacter alkaliphilus is a subtype of ''Athrobacter'' that can degrade lindane and use it as a carbon source. It utilizes acid phosphatase, alkaline phosphatase, alpha-galactosidase, catalase, Pyrazinamidase, and urease. It is commonly found in volcanic rock at an optimal pH of 8.5, 3-7% NaCl, and a temperature of 30 °C. It cannot form

spores In biology, a spore is a unit of sexual or asexual reproduction that may be adapted for dispersal and for survival, often for extended periods of time, in unfavourable conditions. Spores form part of the life cycles of many plants, algae, ...

for reproduction.

Relevance to broader system

The genus ''Arthrobacter'' is a member of the family

and compared to other genera of the family, it contains the highest number of species. This contributes to the fact that species within ''Arthrobacter'' are metabolically versatile and can be found in diverse

environment Environment most often refers to: __NOTOC__ * Natural environment, all living and non-living things occurring naturally * Biophysical environment, the physical and biological factors along with their chemical interactions that affect an organism or ...

s. Understanding this genus is essential to understanding the impact each has on its environment. The primary impact each has is its ability to degrade different environmental

pollutants A pollutant or novel entity is a substance or energy introduced into the environment that has undesired effects, or adversely affects the usefulness of a resource. These can be both naturally forming (i.e. minerals or extracted compounds like o ...

. One such pollutant, lindane, has shown to accumulate in the adipose tissue of different organisms and is very toxic to aquatic organisms and somewhat toxic to mammals and birds. Arthrobacter Alkaliphilus’ ability to degrade lindane can then have a major impact on its

ecosystem An ecosystem (or ecological system) consists of all the organisms and the physical environment with which they interact. These biotic and abiotic components are linked together through nutrient cycles and energy flows. Energy enters the syst ...

References

External links