A Novel Exopolymer-Producing Bacterium, Paracoccus zeaxanthinifaciens subsp. payriae, Isolated from a ?Kopara? Mat Located in Rangiroa, an Atoll of French Polynesia

Abstract

An aerobic, mesophilic and heterotrophic marine bacterium designated RA19, able to produce two different exocellular polymers and zeaxanthin, was isolated from a French polynesian bacterial mat (localy named "kopara") situated in the atoll of Rangiroa. This microorganism, on the basis of its phenotypical features and the genotypic investigations, can be clearly assigned to the Parococcus zeaxanthinifaciens species and the name Parococcus zeaxanthinifaciens subsp. payriae is proposed. Optimal growth occurs between 30 degrees C and 35 degrees C, at pH between 6.5 and 7.5 and at ionic strength between 20 and 40 g/L of NaCl. The guanine-plus-cytosine content of DNA was 65.6%. This bacterium excreted, under laboratory conditions, two different polymers: a water-soluble exopolysaccharide (EPSI) consisting of 5 different sugars and a non-water-soluble macromolecule assumed to be of a glycoproteinic nature. The high sulfate content of the EPS1 and preliminary biological tests clearly showed that applications could be found in the very near future for both polymers in the cosmetic area. Their contribution to the viscous laminated microbial mat locally called "kopara" can be also mentioned.

Investigations into the uptake of copper, iron and selenium by a highly sulphated bacterial exopolysaccharide isolated from microbial mats

“…Enrichment cultures were purified on marine agar 2216E (MA, Difco Laboratories, Detroit, MI). Strain RA19 was selected because of its ability to exhibit a swarming mucoid phenotype on marine agar 2216E supplemented with 30 g l -1 of glucose along with a pigment further identified as pure all-trans-zeaxanthin [19].…”

“…This strain, P. zeaxanthinifaciens subsp. payriae, has been deposited in the Collection Nationale de Culture de Microorganismes (Institut Pasteur, Paris, France) as strain CNCM I-2926 [19]. The crude chemical composition included approximately 48% (w/w) neutral sugars, 8% (w/w) uronic acid, 8% (w/w) acetate and 27% (w/w) sulphate [19].…”

“…payriae, has been deposited in the Collection Nationale de Culture de Microorganismes (Institut Pasteur, Paris, France) as strain CNCM I-2926 [19]. The crude chemical composition included approximately 48% (w/w) neutral sugars, 8% (w/w) uronic acid, 8% (w/w) acetate and 27% (w/w) sulphate [19]. This study was conducted to investigate the ability of EPS produced by strain RA19 to bind heavy metals, such as copper and iron, as a first step in assessing the biotechnological potential of this EPS.…”

Role of Polyphosphates in Microbial Adaptation to Extreme Environments

“…Cellular water loss imposes a series of structural, physiologic, and biochemical challenges that microbes must overcome in order to survive. Several studies have suggested that for microorganisms found in extreme environments exposed to hypersalinity, desiccation and UV radiation are capable of producing large amounts of extracellular exopolymers (62,67). Extracellular polymers enhance biofilm formation and may be major components of the water loss VOL.…”

A novel mcl PHA-producing bacterium, Pseudomonas guezennei sp. nov., isolated from a ‘kopara’ mat located in Rangiroa, an atoll of French Polynesia

“…In November 2001, many samples of 'kopara' were collected from the different microbial mats located on the atoll of Rangiroa (Raguénès et al 2004). Enrichment cultures were purified on Marine Agar 2216E (Difco Laboratories, Detroit, MI, USA).…”