Assignment of Pseudomonas sp. strain E-3 to Pseudomonas psychrophila sp. nov., a new facultatively psychrophilic bacterium

Abstract

A facultatively psychrophilic bacterium, previously described as Pseudomonas sp. strain E-3, has been reassigned by phenotypic characterization, chemotaxonomic analysis, DNA-DNA hybridization, and 16S rRNA gene phylogenetic analysis. The organism was a gram-negative, aerobic. straight rod with polar flagella. It was catalase positive and oxidase positive, able to grow at -1 degree C but not at 40 degree C, and produced acid from D-glucose under aerobic conditions. The major isoprenoid quinone was ubiquinone-9, and the DNA G + C content was 57.2 mol%. Phylogenetic analysis based on 16S rRNA gene sequencing indicated that the bacterium is a member of the genus Pseudomonas and was closest to Pseudomonas fragi. Determination of the DNA-DNA relatedness between strain E-3 and P. fragi revealed too low a level of homology (47.9%-51.3%) to identify them as the same species. On the basis of phenotypic characteristics, phylogenetic analysis, and DNA-DNA relatedness data, it is concluded that strain E-3 represents an individual species. Accordingly, the name Pseudomonas psychrophila is proposed. The type strain is E-3T (= JCM 10889).

Microbial Successions Are Associated with Changes in Chemical Profiles of a Model Refrigerated Fresh Pork Sausage during an 80-Day Shelf Life Study

“…Although multiple species of Pseudomonas (P. poae, P. azotoformans, P. stutzeri, P. syringae, P. lini, and P. psychrophila) were present at low levels (ϳ0.005 to 0.01%) at time zero, only P. lini and P. psychrophila showed a dramatic increase in abundance during phase I. Strains belonging to each of these species are known to be psychrotrophic, and we would therefore have expected all six of these species to grow at refrigeration temperatures (25)(26)(27)(28)(29), leaving open the question as to why only P. lini and P. psychrophila showed such a dramatic growth in the sausage. It is possible that P. poae, P. azotoformans, and P. stutzeri are selectively inhibited by the antimicrobial characteristics of the spice blend.…”

Microorganisms Associated with Uranium Bioremediation in a High-Salinity Subsurface Sediment

“…Attempts to isolate some of the Pseudomonas and Desulfosporosinus species which might be responsible for metal reduction in the site 854 sediments have as yet been unsuccessful. However, there are strains of Pseudomonas (9,16) and Desulfosporosinus (10) that can grow at high salinities, and organisms in these genera are known to be capable of Fe(III) reduction (5,10). Thus, further attempts to isolate the salt-tolerant metal-reducing organisms and study their physiology seem warranted in order to provide insights into the physiological factors controlling the rate and extent of metal reduction in highly saline subsurface environments.…”

Shelf life evaluation of fresh-cut red chicory subjected to different minimal processes

“…The highest presence of P. fluorescens in fresh cut products rather than entire leaves is not surprising, because the dominance of this species over the total bacterial population of fresh-cut leafy vegetables is well known (Myszka et al, 2017). P. psychrophila is characterized by a trans-unsaturated fatty acid profile necessary for the exposition to low temperatures (Yumoto et al, 2001) justifying its presence in refrigerated vegetables.…”