Agarivorans gilvus sp. nov. isolated from seaweed

Abstract

A novel agarase-producing, non-endospore-forming marine bacterium, WH0801 T , was isolated from a fresh seaweed sample collected from the coast of Weihai, China. Preliminary characterization based on 16S rRNA gene sequence analysis showed that WH0801 T shared 96.1 % similarity with Agarivorans albus MKT 106 T , the type species of the genus Agarivorans. A polyphasic taxonomic study was conducted and confirmed the phylogenetic affiliation of strain WH0801 T to the genus Agarivorans. Isolate WH0801 T produces light-yellow-pigmented colonies; cells are Gram-stain-negative, straight or curved rods, which are motile with a single polar flagellum. Strain WH0801 T grew in 0.5-5 % NaCl, with optimum growth at 3 % NaCl, and its optimal pH and cultivation temperature were 8.4-8.6 and 28-32 6C, respectively. Data from biochemical tests, whole-cell fatty acid profiling, 16S rRNA gene sequence studies and DNA-DNA hybridization clearly indicated that isolate WH0801 T represented a novel species within the genus Agarivorans, for which the name Agarivorans gilvus sp. nov. is proposed. The type strain of Agarivorans gilvus sp. nov. is WH0801 T (5NRRL B-59247 T 5CGMCC 1.10131 T ).The genus Agarivorans was created by Kurahashi & Yokota (2004) to accommodate Gram-negative, strictly aerobic and agar-hydrolysing species. The genus is affiliated with the class Gammaproteobacteria and presently contains only the type species, Agarivorans albus. The Agarivorans albus strains studied by Kurahashi & Yokota were agarolytic and isolated from healthy marine organisms collected from the coast of the Kanto area in Japan. Many novel agardegrading bacterial species have been isolated from marine environments, where they occur as part of the indigenous flora. For example, Simiduia agarivorans, Aliagarivorans marinus, Aliagarivorans taiwanensis and Tamlana agarivorans were isolated from seawater samples (Shieh et al., 2008;Jean et al., 2009;Yoon et al., 2008); Psychromonas agarivorans, Microbulbifer agarilyticus and Marinimicrobium agarilyticum were found in marine sediment samples (Hosoya et al., 2009;Miyazaki et al., 2008;Lim et al., 2006); and Salegentibacter agarivorans was recovered from a species of sponge (Nedashkovskaya et al., 2006). The widespread occurrence of agar-degrading bacteria is probably best explained by their likely role in the carbon cycle involving the breakdown of agar and other sulfated galactans (Armisen & Galactas, 1987;Pomin, 2010), which form a significant component of the cell walls of red and green algae, the egg jelly coating of certain sea urchin species, and the outer tunics of ascidians (Pomin, 2010). We examined the diversity of agarolytic marine bacteria isolated from various marine samples such as seawater, sediment, seaweed and some marine animal samples that were taken from waters off various locations across coastal China. As a result of these efforts, we have already described one new genus, Gilvimarinus (Du et al., 2009). Here, we report the taxonomic characteristics of a novel species of the genus Agariv...

A high-throughput solid phase screening method for identification of lignocellulose-degrading bacteria from environmental isolates

“…The ability to depolymerize agar for use as a carbon source has been reported for a number of microbes, including microorganisms that can also utilize lignocellulose (Du et al 2011;Ekborg et al 2006;Kim et al 2011;Shin et al 2010). The capacity of microbes to depolymerize agar allows for growth of the microbe in agar based plate assays, which leads to false positives in screens for lignocellulolytic microorganisms.…”

Draft Genome Sequence of Agarivorans albus Strain MKT 106 T , an Agarolytic Marine Bacterium

“…Members of the genus Agarivorans , which is currently composed of two species, are Gram-negative, strictly aerobic, and agar-hydrolyzing bacteria (1, 2). Agarivorans albus , the type species of the genus Agarivorans , was isolated by Kurahashi and Yokota (1) from the intestines of healthy marine creatures (molluscs and protochordata) that were collected from the coast of the Kanto area in Japan.…”

Complete genome sequence of Agarivorans gilvus WH0801T, an agarase-producing bacterium isolated from seaweed

“…Recently, a novel strain WH0801 T was isolated from the surface of seaweed in the shallow coastal region of Weihai, China, proposed to be a new species Agarivorans gilvus (Du et al, 2011). Two novel ␤-agarase genes, AgWH50A and AgWH50C, and a novel ␣-neoagarobiose hydrolase gene, AgaWH117, were cloned from this strain by our group (Liu et al, 2014a(Liu et al, ,b, 2015.…”