A Microbial Biorealm page on the genus Pseudomonas baetica
Higher order taxa
Kingdom: Bacteria Phylum: Proteobacteria Class: Gammaproteobacteria Order: Pseudomonadales Family: Pseudomonadaceae
Description and significance
P. baetica is an irregularly rod-shaped bacterium found in the livers of the flatfish species known as wedge sole (Dicologlossa cuneata). The bacterium is motile (unknown means), and gram negative. There are five identified strains of this microbe, all identified from the wedge sole, and referred to as “wedge sole isolates”: a390T, a391, a393, a398 and a399. The main difference between P. baetica and the eight other strains to which it was compared is the ability to grow at 6% NaCl. This bacterium is responsible for killing numerous wedge sole. Wedge sole are a financially significant fish species, cultured in southern Spain for food production (Lopez et. al. 2012).
Closest genetic relation by 16S rRNA sequence is P. jessenii CIP 105274T (99.5% similar), and by gyrB gene sequence is P. marginalis ATCC 10844T (94.6% similar). By rpoD gene sequencing, P. baetica is most closely related to P. fluorescens at 95.1% similarity. P. baetica was confirmed as a novel species by DNA-DNA hybridization. When a390T was hybridized with other Pseudomonas species, comparisons were well below the “threshold value for species delineation of 70%”, all being less than 47.6% similar. Alternatively, hybridizations between the type strain and other “wedge-sole isolates” were between 74 and 96% (Lopez, et. al. 2012). A genomic sequencing of 10,000bp is in the “Improved High-Quality Draft” stage on JGI-DOE. The PI is Joyce E. Lauper, and the information was added automatically to JGI Gold on April 6, 2015 automatically as project ID: Gp0112912
Cell and colony structure
Gram-negative, thus very little peptidoglycan in cell membrane. As previously known for species of Pseudomonas s.s., an examination of Fatty acid methyl esters (FAMEs) gives “a considerable amount of 12:0 fatty acids and the detection of only trace amounts of 14:0 fatty acids” (Lopez, et. al. 2012). Colonies are described by Lopez, et. al. as “small (up to approx 0.5mm in diameter after 48h incubation), round and whitish.”
P. baetica is an aerobic bacterium, utilizing oxidative metabolism, and it produces cytochrome oxidase and catalase. According to the studies performed by Lopez, et. al., is capable of utilizing as carbon sources. this microbe is haemolytic on sheep blood agar. Also, the use of glucose and mannose produces gas. Lopez states that P. baetica is a denitrifier, though doesn’t indicate whether any anaerobic or fermentative activity is present.
Found in the liver of wedge-sole, Dicologlossa cuneata. P. baetica is a denitrifier, meaning it rearranges bioavailable nitrogenous compounds into atmospheric nitrogen gas, N2.P. baetica can grow in temperatures ranging from 4-30 degrees Celsius, making it a mesophile, and salinity ranging from 0-6% NaCl.
P. baetica is pathogenic to wedge sole, Dicologlossa cuneata. Virulence of the test strain was tested by intraperitoneal injection and immersion. When tested, these experiments produced 100% mortality over three days by injection and 10% mortality in 18 days by immersion. P. baetica is sensitive to novobiocin, and resistant to the vibriostatic agent O/129 and ampicillin (Lopez, et. al.).
López, Jose R. and Diéguez, Ana L. and Doce, Alejandra and De la Roca, Elena and De la Herran, Roberto and Navas, Jose I. and Toranzo, Alicia E. and Romalde, Jesus L.","Pseudomonas baetica sp. nov., a fish pathogen isolated from wedge sole, Dicologlossa cuneata (Moreau)." International Journal of Systematic and Evolutionary Microbiology, 2012, vol.62, pg.874-882, http://ijs.microbiologyresearch.org/content/journal/ijsem/10.1099/ijs.0.030601-0
GOLD Genome Online Database. JGI, n.d., Dec. 8, 2015, https://gold.jgi.doe.gov/projects?id=Gp0112912
Edited by Mike Sullivan, Jr. of Dr. Lisa R. Moore, University of Southern Maine, Department of Biological Sciences, http://www.usm.maine.edu/bio