Phenotypic and genotypic characterization of H2S‐positive and H2S‐negative strains of Shewanella baltica isolated from spoiled whiting (Merlangius merlangus). (21st August 2014)

• Record Type: Journal Article
• Authors: Dehaut, A.; Midelet‐Bourdin, G.; Brisabois, A.; Duflos, G.
• Is Part Of: Letters in applied microbiology. Volume 59:Number 5(2014:Nov.)
• Page Start: 542
• Page End: 548
• Publication Date: 2014-08-21
• Subjects: Microbiology -- Periodicals; 660.62
• DOI: 10.1111/lam.12312
• Languages: English
• ISSNs: 0266-8254

Abstract

<abstract abstract-type="main" id="lam12312-abs-0001"> <title>Abstract</title> <sec id="lam12312-sec-1001" sec-type="section"> <p>Four strains were isolated from a spoiled whiting (<italic>Merlangius merlangus</italic>). All of them were able to grow aerobically from 4 to 30°C and also able to develop anaerobically in the presence of trimethylamine <italic>N</italic>‐Oxide (TMAO) at 25°C. Biochemical characterization did not allow identification of the strains species but showed that one of the four strains was unable to produce H<sub>2</sub>S. Two strains synthetized an ornithine decarboxylase being potential putrescine producers. Results of carbon source use highlighted that the four strains were able to use citrate and <sc>d</sc>‐sucrose and one strain was not able to use <sc>l</sc>‐arabinose. Genotypic characterization of the strains thanks to 16S rRNA and <italic>gyrB</italic> partial gene sequencing led to their identification as members of <italic>Shewanella baltica</italic> species. These observations suggest that H<sub>2</sub>S production may not be the most appropriate screening parameter for <italic>Shewanella</italic> species and further to monitor the development of spoilage flora.</p> </sec> <sec id="lam12312-sec-1002" sec-type="section"> <title>Significance and Impact of the Study</title> <p> <italic>Shewanella</italic> is a complex genus composed of numerous and heterogeneous species. One of them <italic>Shewanella baltica</italic> has previously been described as one of the most important H<sub>2</sub>S‐producing bacterial species in iced stored fish and may act as spoilage organism through the reduction of trimethylamine <italic>N</italic>‐Oxide (TMAO). Four strains of <italic>S. baltica</italic> were isolated from spoiled whiting (<italic>Merlangius merlangus</italic>), and description of three H<sub>2</sub>S‐positive strains and one H<sub>2</sub>S‐negative strain of <italic>S. baltica</italic> is highlighted in this short paper. Consequently, H<sub>2</sub>S production might not be the most appropriate screening parameter to assess the development of spoilage organisms.</p> </sec> </abstract>