Draft Genome Sequence of Serratia rubidaea, a Potential Opportunistic Pathogen Isolated from Food in Italy

Serratia rubidaea has emerged in recent years as an opportunistic nosocomial pathogen. Here, we present the draft genome sequence of an isolate derived from an industrial meat food product purchased in a large-scale retail store that revealed fluoroquinolone, β-lactam, and aminoglycoside resistance genes and two different host-unspecific prophages.

Evidence for Enhanced Dissipation of Chlorpyrifos in an Agricultural Soil Inoculated with Serratia Rubidaea Strain ABS 10

Important mineralization of 14C-chlorpyrifos was found in a Tunisian soil exposed repeatedly to this insecticide. A bacterial strain able to grow in minimal salt medium (MSM) supplemented with 25 mg L− 1 of chlorpyrifos was isolated from this soil. It was characterized as Serratia rubidaea strain ABS 10 using morphological and biochemical analyses, as well as 16S rRNA sequencing. In liquid culture S. rubidaea stain ABS 10 was able to almost entirely dissipate chlorpyrifos within 48 hours of incubation. Although, S. rubidaea strain ABS 10 was able to grow on MSM supplemented with chlorpyrifos and to dissipate it in liquid culture, it was not able to mineralize 14C-chlorpyrifos. Therefore, one can conclude that the dissipation capability of this bacteria might be attributed to its capacity to adsorb CHL. In both non-sterile and sterile soil inoculated with S. rubidaea strain ABS 10, chlorpyrifos was more rapidly dissipated than in respective controls.

Halotolerant Endophytic Bacterium Serratia rubidaea ED1 Enhances Phosphate Solubilization and Promotes Seed Germination

Quinoa is renowned for its nutritional value and ability to withstand harsh environmental conditions such as salinity. In the present work, we isolated 34 phosphate solubilizing endophytic bacteria associated with the roots of quinoa plants. Based on phosphate solubilization efficiency and biochemical characterization, we selected one isolate named ED1. Ribotyping using partial 16S RNA gene analysis revealed that the selected isolate shares 99.7% identity with Serratia rubidaea. Plant growth promoting (PGP) studies showed that the ED1 strain solubilized complexed forms of phosphate (Ca3(PO4)2). Zinc release from ZnO, Zn3(PO4)2, or ZnCO3 revealed the efficient ZnO solubilization by the ED1 strain. Except for proteases, the strain ED1 produced siderophores, cellulase, ammonia and exhibited oligonitrophilic features. Indole acetic acid (IAA) production was detected with and without the L-tryptophan precursor. Next, we demonstrated that the ED1 strain tolerated 1.5 M NaCl final concentration and exhibited intrinsic resistance to seven antibiotics frequently prescribed for medical use. Moreover, we found that ED1 strain withstood 2 mg/L of Cadmium and 1 mg/L of either Nickel or Copper. Furthermore, we observed that S. rubidaea ED1 stimulated quinoa seeds germination and seedlings growth under salt stress conditions. Lastly, we discuss the advantages versus disadvantages of applying the S. rubidaea ED1 strain as a beneficial agent for salty and/or heavy metals contaminated soils.

Short Communication: Serratia rubidaea as contaminant in laboratory environment

Virgianti DP. 2020. Short Communication: Serratia rubidaea as contaminant in laboratory environment. Nusantara Bioscience 13: 47-51. There have been many cases of bacterial contamination in the laboratory. The bacterial genera identified as contaminants are Bacillus, Staphylococcus, Micrococcus, Pseudomonas, Shigella and Serratia. These bacteria are classified as non-pathogenic and pathogenic bacteria that can interfere with the test and potentially develop false-positive results. The present research has shown that red-colored contaminant bacteria develop in unused sterile media in our laboratory. Based on related information, Serratia marcescens is a red bacterial species that have been reported as a contaminant in the laboratory. The purpose of this study was to identifiy contaminant bacteria at the molecular level. Based on the phylogenetic characterization using the 16S rDNA gene region, this red contaminant bacterium was identified as Serratia rubidaea.