Figure - available from: PLOS ONE
This content is subject to copyright.
Phylogenetic tree highlighting the position of S. marcescens RSC-14 with other closely related species within the genus of Serratia The phylogenetic tree was constructed based on concatenated sequences of 16S rRNA, gyrB, and rpoB genes aligned in ClustalW2 using the neighbor-joining algorithm in CLC Main Workbench and rooted with Photorhabdus luminescens subsp. laumondii TTO1. All Serratia species clustered together and were distinct from other Enterobacteriaceae. The tree also highlights the close relationship of S. marcescens RSC-14 strain with the S. marcescens type strain WW4.
Source publication
Serratia marcescens RSC-14 is a Gram-negative bacterium that was previously isolated from the surface-sterilized roots of the Cd-hyperaccumulator Solanum nigrum. The strain stimulates plant growth and alleviates Cd stress in host plants. To investigate the genetic basis for these traits, the complete genome of RSC-14 was obtained by single-molecule...
Citations
... The cluster comprising the anthranilate synthase subunits TrpE and TrpG, involved on the conversion of chorismate to anthranilate, an anthranilate-phosphoribosyl transferase TrpD which insert a phosphoribosyl phyrophosphate (PPi) to yield N-(5'-phosphoribosyl)-anthranilate, a bifunctional phosphoribosyl-anthranilate isomerase/indoleglycerol phosphate synthase TrpCF which catalyse the isomerization and subsequent conversion to indole 3-glycerol phosphate and the tryptophan synthase subunits TrpB and TrpA that converts indole 3-glycerol phosphate into L-tryptophan (Kagan et al. 2008). Despite the accessorial enzymes involved on the conversion of tryptophan to IAA were not grouped along with or detected in the genomic neighbourhood of the trpEG-DCFBA gene cluster, the genomes of the three strains contained the ipdC gene encoding for indole-pyruvate decarboxylase, a key enzyme in the synthesis of IAA from tryptophan through the intermediary indole pyruvate (IPyA) (Khan et al. 2017). ...
Despite being one of the most abundant elements in soil, phosphorus (P) often becomes a limiting macronutrient for plants due to its low bioavailability, primarily locked away in insoluble organic and inorganic forms. Phosphate solubilizing and mineralizing bacteria, also called phosphobacteria, isolated from P-deficient soils have emerged as a promising biofertilizer alternative, capable of converting these recalcitrant P forms into plant-available phosphates. Three such phosphobacteria strains—Serratia sp. RJAL6, Klebsiella sp. RCJ4, and Enterobacter sp. 198—previously demonstrated their particular strength as plant growth promoters for wheat, ryegrass, or avocado under abiotic stresses and P deficiency. Comparative genomic analysis of their draft genomes revealed several genes encoding key functionalities, including alkaline phosphatases, isonitrile secondary metabolites, enterobactin biosynthesis and genes associated to the production of indole-3-acetic acid (IAA) and gluconic acid. Moreover, overall genome relatedness indexes (OGRIs) revealed substantial divergence between Serratia sp. RJAL6 and its closest phylogenetic neighbours, Serratia nematodiphila and Serratia bockelmanii. This compelling evidence suggests that RJAL6 merits classification as a novel species. This in silico genomic analysis provides vital insights into the plant growth-promoting capabilities and provenance of these promising PSRB strains. Notably, it paves the way for further characterization and potential application of the newly identified Serratia species as a powerful bioinoculant in future agricultural settings.
... The cluster comprising the anthranilate synthase subunits TrpE and TrpG, involved on the conversion of chorismate to anthranilate, an anthranilate-phosphoribosyl transferase TrpD which insert a phosphoribosyl phyrophosphate (PPi) to yield N-(5'-phosphoribosyl)-anthranilate, a bifunctional phosphoribosyl-anthranilate isomerase/indoleglycerol phosphate synthase TrpCF which catalyse the isomerization and subsequent conversion to indole 3-glycerol phosphate and the tryptophan synthase subunits TrpB and TrpA that converts indole 3-glycerol phosphate into Ltryptophan [32]. Despite the accessorial enzymes involved on the conversion of tryptophan to IAA were not grouped along with or detected in the genomic neighbourhood of the trpEGDCFBA gene cluster, the genomes of the three strains contained the ipdC gene encoding for indole-pyruvate decarboxylase, a key enzyme in the synthesis of IAA from tryptophan through the intermediary indole pyruvate (IPyA) [33]. ...
Despite being one of the most abundant elements in soil, phosphorus (P) often becomes a limiting macronutrient for plants due to its low bioavailability, primarily locked away in insoluble organic and inorganic forms. Phosphate solubilizing and mineralizing bacteria, also called phosphobacteria, isolated from P-deficient soils have emerged as a promising biofertilizer alternative, capable of converting these recalcitrant P forms into plant-available phosphates. Three such phosphobacteria strains - Serratia sp. RJAL6, Klebsiella sp. RCJ4, and Enterobacter sp. 198 - previously demonstrated their particular strength as plant growth promoters for wheat, ryegrass, or avocado under abiotic stresses and P deficiency. Comparative genomic analysis of their draft genomes revealed several genes encoding key functionalities, including alkaline phosphatases, isonitrile secondary metabolites, enterobactin biosynthesis and genes associated to the production of indole-3-acetic acid (IAA) and gluconic acid. Moreover, overall genome relatedness indexes (OGRIs) revealed substantial divergence between Serratia sp. RJAL6 and its closest phylogenetic neighbors, Serratia nematodiphila and Serratia bockelmanii. This compelling evidence suggests that RJAL6 merits classification as a novel species. This in silico genomic analysis provides vital insights into the plant growth-promoting capabilities and provenance of these promising PSRB strains. Notably, it paves the way for further characterization and potential application of the newly identified Serratia species as a powerful bioinoculant in future agricultural settings.
... The primers cadSM-F, cadSM-R, zntA-F and zntA-R were designed with the Primer-BLAST tool (Ye et al. 2012), based on two heavy metal resistance genes present in the genome of Serratia marcescens RSC-14 , which is deposited in GenBank under accession number NZ_CP012639.1. The locus tags for the two target genes are AN479_RS08980 (czc gene, Khan et al. 2017) and AN479_ RS21320 (zntA gene, Khan et al. 2017). ...
... The primers cadSM-F, cadSM-R, zntA-F and zntA-R were designed with the Primer-BLAST tool (Ye et al. 2012), based on two heavy metal resistance genes present in the genome of Serratia marcescens RSC-14 , which is deposited in GenBank under accession number NZ_CP012639.1. The locus tags for the two target genes are AN479_RS08980 (czc gene, Khan et al. 2017) and AN479_ RS21320 (zntA gene, Khan et al. 2017). ...
Cadmium (Cd) presence and bioavailability in soils is a serious concern for cocoa producers. Cocoa plants can bioaccumulate Cd that can reach humans through the food chain, thus posing a threat to human health, as Cd is a highly toxic metal. Currently, microbiologically induced carbonate precipitation (MICP) by the ureolytic path has been proposed as an effective technique for Cd remediation. In this work, the Cd remediation potential and Cd resistance of two ureolytic bacteria, Serratia sp. strains 4.1a and 5b, were evaluated. The growth of both Serratia strains was inhibited at 4 mM Cd(II) in the culture medium, which is far higher than the Cd content that can be found in the soils targeted for remediation. Regarding removal efficiency, for an initial concentration of 0.15 mM Cd(II) in liquid medium, the maximum removal percentages for Serratia sp. 4.1.a and 5b were 99.3% and 99.57%, respectively. Their precipitates produced during Cd removal were identified as calcite by X-ray diffraction. Energy dispersive X-ray spectroscopy analysis showed that a portion of Cd was immobilized in this matrix. Finally, the presence of a partial gene from the czc operon, involved in Cd resistance, was observed in Serratia sp. 5b. The expression of this gene was found to be unaffected by the presence of Cd(II), and upregulated in the presence of urea. This work is one of the few to report the use of bacterial strains of the Serratia genus for Cd remediation by MICP, and apparently the first one to report differential expression of a Cd resistance gene due to the presence of urea.
... PSM 14 was round but smooth, and they all had the same shapes in morphology. The organisms were identified as Serritia, Pseudomonas and Klebsiella when subjected to gram staining (Fig. 1), biochemical tests as per Bergey's manual of systematic bacteriology ( Previous studies found phosphatase-coding genes in Serratia marcescens and Pseudomonas [39]. Furthermore, Lavania and Nautiyal (2013) discovered that the soil isolate S. marcescens NBRI1213 is an effective phosphate solubilizer as well as a possible plant growth promoter [40]. ...
Phosphate-solubilizing microbes (PSMs) play a crucial role in converting insoluble phosphates into soluble forms, thereby enhancing phosphorus availability to plants. In this study, we aimed to isolate and identify PSMs collected from rhizospheric soil. The isolated strain was identified as Serratia based on colony characteristics and biochemical analysis. Furthermore, we explored the phosphatase activity of 77.26±0.46 U/ml, optimization of growth conditions for crude acid phosphatase was found to be temperature of 45ºC, pH was 5 and glucose and ammonium sulphate served as good substrates for carbon and nitrogen sources. Partial purification of acid phosphatase by salt precipitation and dialysis gave a yield of 36.68±0.05% compared to crude. Acetic acid was vigorously produced by the isolate, reaching concentrations of 40.41±0.35 mg/L compared to other organic acids analysis by GC-MS. The production of other plant growth-promoting enzymes and hormones were identified. The antagonistic activity as biocontrol agent of the isolate was performed on plant pathogens. These findings contribute to our understanding of microbial-driven processes for sustainable agriculture and highlight the potential application of PSMs in enhancing phosphorus availability and plant growth in agricultural systems.
... Our findings illustrated that the accumulation of root/shoot Cd was decreased by the inoculation of PGPR which in response increased the fresh and dry biomass of plants in Cd contaminated soil (Hashmat et al., 2023;Abbas et al., 2023). These PGPB generate IAA via the upregulation of genes involved in IAA generation and solubilize phosphate in plants, which increases cell elongation/division and enables plants to attain higher growth (Khan et al., 2017;Chi et al., 2022). Further, these Cd tolerant strains also increased the solubilization of soil nutrients (N, P, and K) which are necessary constituents of plant leaf chlorophyll and biomass (Qin et al., 2020). ...
ABSTRACT
Heavy metals contamination of soil is increasing rapidly due to prompt in urbanization and industrialization.
Recently, cadmium (Cd) pollution has emerged as a severe menace to plant and human health, while the use of
plant growth promoting rhizobacteria (PGPR) has appeared as an economical approach for bioremediation of Cd
toxicity in crop plants. In this study, the effect of Serratia sp. CP-13 inoculation on two maize cultivars in pre-Cd
(0, 5, 12, 18, 26, 30 µM) spiked soil was evaluated. The combined effect of soil Cd and CP-13 application was
assessed through the analysis of seed germination, plant biomass, phytohormones, gas exchange attributes,
antioxidant production, plant Cd, and nutrient uptake in two (Sahiwal-2002, MMRI-Yellow) maize cultivars. Our
outcomes exposed that single treatment of Cd-spiked soil significantly downregulates seed germination, plant
biomass, plant nutrients, photosynthetic pigments, indole acetic acid (IAA), total protein, proline, total soluble
sugar (TSS), stomatal conductance, transpiration rate, net photosynthesis, and antioxidant production, together
with upregulating malondialdehyde (MDA), relative membrane permeability (RMP), abscisic acid (ABA), and Cd
uptake in maize cultivars. However, this response of the maize crop against Cd-spiked soil was found to be
maximal in Sahiwal-2002 at 30 µM Cd. Furthermore, the inoculation of Cd-resistant CP-13 significantly upre�gulates the plant accumulation of biomass, seed germination, antioxidants, IAA, gas exchange attributes,
photosynthetic pigments, plant physiology, and nutrient uptake and downregulates the MDA, RMP, ABA, and
root/shoot Cd accretion in two cultivars of maize. Moreover, this CP-13 based upregulation of plant growth was
found to be cultivar (Sahiwal-2002) and Cd treatment (30 µM) specific by controlling the accumulation of lipid
peroxidation, phytohormone content, and Cd detoxification. Further, our results indicate that the CP-13 might be
a promising and cost effective future biofertilizer for bioremediation of soil Cd
... DW1 isolated from the rhizospheric soil of eggplant helps to ameliorate salt stress and improve mineral uptake positively (Fu et al. 2010).Serratia marcescens S14 isolated from endosphere of Solanum sodomaeum can promote the growth and development of tomato and control Fusarium wilt (Aydi-Ben-Abdallah et al. 2020). Serratia marcescens RSC-14 isolated from Solanum nigrum alleviates cadmium stress (Khan et al. 2017). These innovative methods of using microorganism in enhancing the agricultural production are recently gaining more interest. ...
The current study was aimed to isolate, identify and evaluate the potential endophytic bacterial strains inhabiting Solanum melongena L. for plant growth promotion (PGP) and biocontrol against important soil-borne plant pathogenic fungi. A total of 36 endophytic bacteria isolated from Solanum melongena L. (Eggplant) were characterized for qualitative PGP traits. Most promising strains SS_BS01, SS_BL08, SS_BL12 were identified using biochemical characteristics and 16S rDNA sequencing as Serratia marcescens (SS_BS01), Bacillus amyloliquefaciens (SS_BL08) and Pseudomonas sp. (SS_BL12) respectively. In addition, quantitative assays and antagonistic activities proved Bacillus amyloliquefaciens strain SS_BL08 efficient at all respects with maximum 145.8 ± 4.5µg mL-1(after 192 h) phosphate solubilization, 25.0 ± 1.6µg (5mg mL-1 L-tryptophan) IAA production and more than 60 % inhibition against selected phytopathogens. Furthermore, germination percentage, vigour index and seedling growth (root and shoot length) were also significantly increased. Selected endophytic bacterial strains of eggplant demonstrated promising results and Bacillus amyloliquefaciens strain SS_BL08, effective in promoting plant development and biocontrol, could be employed as bio-fertilizer and biocontrol agent for solanaceous crops in organic agriculture practice.
... Uniquely, many genes responsible for heavy metal tolerance are naturally found in some bacteria before exposure, suggesting that acquired tolerance is a strain's ability to be further enhanced. As reported in one paper [57], three genes encoding Cd/Pb/Hg/Zn-transporting ATPase, as well as three putative genes encoding the Zn/Co/Cd resistance protein CzcD, are naturally present in Serratia marcescens isolated from roots of Solanum nigrum. Although this bacterium had no previous exposure to heavy metals, the strain developed tolerance when exposed to Cd. ...
... Although this bacterium had no previous exposure to heavy metals, the strain developed tolerance when exposed to Cd. The findings [57] are further supported by the work of Kotoky et al. [58], where Serratia marcescens was found to be highly resistant to Cd by utilizing the glutathione-S-transferase mechanism for detoxification [58]. There are similarities between the attitudes expressed by consortium JR3 in this study and those described by Khan et al. [57]. ...
... The findings [57] are further supported by the work of Kotoky et al. [58], where Serratia marcescens was found to be highly resistant to Cd by utilizing the glutathione-S-transferase mechanism for detoxification [58]. There are similarities between the attitudes expressed by consortium JR3 in this study and those described by Khan et al. [57]. The ability to decolorize RR120 in the presence of cadmium can probably be attributed to the Serratia marcescens strain MM06, as this genus is known for its metal-tolerant capability due to the presence of metal-efflux genes [59]. ...
Juru River is one of the most polluted rivers in Malaysia. A dye-degrading bacterial consortium has been isolated from the river's sediment. This consortium JR3 consists of Pseudomonas aeruginosa MM01, Enterobacter sp. MM05 and Serratia marcescens MM06, which were able to decolorize up to 700 ppm of the Reactive Red 120 (RR120) dye under optimal conditions with limited substrate available. Substrate inhibition kinetics were investigated, and, based on the best model, Aiba, the maximum growth rate was 0.795 h–1, while the saturation constant and inhibitory constant were 0.185% and 0.14%, respectively. In addition, the influence of various metal ions on the growth and decolorization rate of this bacterial consortium on RR120 was investigated. Chromium showed the weakest effect on the decolorization of 200 ppm RR120, with 73.5% removal and bacterial growth of 11.461 log CFU mL–1. Zinc yielded the second weakest effect, followed by silver and lead, with percentages of RR120 decolorization of 63.8%, 54.6% and 50.5%, respectively. Meanwhile, cadmium, arsenic and copper reduced the decolorization of RR120 in consortium JR3 by half. Mercury strongly inhibited decolorization by 32.5%. Based on the least inhibited heavy metal in RR120 decolorization activity of consortium JR3, the best inhibitory kinetic model was Levenspiel, with a maximum growth rate of 0.632 h–1, while the saturation constant and inhibitory constants were 15.08% and 0.5783%, respectively. The metal-tolerant azo dye-degrading bacterial consortium will be very useful in dye remediation in metal-laden polluted environments.
... Besides nitrogen fixation, Rhizobium produces IAA and Gibberellic Acid in the root nodules, which are two of the most commonly desired auxins in the industry (Purwaningsih et al 2021). In addition to Rhizobium, Serratia is an effective plant growth promoter (Khan et al 2017) and a biological control agent (Ordentlich et al 1987). Rhizobium and Serratia can also produce plant hormones (also known as phytohormones) that regulate plant growth, including auxins, gibberellins, cytokinins, ethylene, and abscisic acid (Patel et al 2015). ...
... An endophytic bacteria Serratia sp. RSC-14 isolated from the roots of S. nigrum displayed phosphate solubilization and produced indole acetic acid [189]. ...
Bacterial endophytes reside within the tissues of living plant species without causing any harm or disease to their hosts. These endophytes can be isolated, identified, characterized, and used as biofertilizers. Moreover, bacterial endophytes increase the plants' resistance against diseases, pests, and parasites, and are a promising source of pharmaceutically important bioactives. For instance, the production of antibiotics, auxins, biosurfactants, cytokinin's, ethylene, enzymes, gibberellins, nitric oxide organic acids, osmolytes, and siderophores is accredited to the existence of various bacterial strains. Thus, this manuscript intends to review the sustainable applications of endophytic bacteria to promote the growth, development, and chemical integrity of medicinal and herbal plants, as well as their role in plant physiology. The study of the importance of bacterial endophytes in the suppression of diseases in medicinal and herbal plants is crucial and a promising area of future investigation.
... The czcD gene was identified by DNA sequencing of S. marcescens RSC-14, which encodes Cd 2+ , Pb 2+ and Zn 2+ resistance proteins responsible for a system of ion efflux to extracellular medium. Other genes encoding proteins related to arsenic resistance and efflux systems and genes coding for superoxide dismutases that are responsible for mechanisms of resistance to the oxidative effects of Mn 2+ , Cu 1+ , Zn 2+ and Fe 2+ have been described (Khan et al. 2017). Moreover, in the genome sequences of S. marcescens published by Iguchi et al. (2014), it was possible to identify the pbrA, zntA and zntR genes, which were used as references to search for homologous sequences and to design primers in the present work. ...
Microorganisms isolated from contaminated areas play an important role in bioremediation processes. They promote heavy metal removal from the environment by adsorbing ions onto the cell wall surface, accumulating them inside the cells, or reducing, complexing, or precipitating these substances in the environment. Microorganism-based bioremediation processes can be highly efficient, low-cost and have low environmental impact. Thus, the present study aimed to select Pb²⁺-resistant bacteria and evaluate the growth rate, biological activity, and the presence of genes associated with metal resistance. Serratia marcescens CCMA 1010, that was previously isolated from coffee processing wastewater, was selected since was able to growth in Pb²⁺ concentrations of up to 4.0 mM. The growth rate and generation time did not differ from those of the control (without Pb²⁺), although biological activity decreased in the first hour of exposure to these ions and stabilized after this period. The presence of the zntR, zntA and pbrA genes was analysed, and only zntR was detected. The zntR gene encodes a protein responsible for regulating the production of ZntA, a transmembrane protein that facilitates Pb²⁺ extrusion out of the cell. S. marcescens CCMA 1010 demonstrated a potential for use as bioindicator that has potential to be used in bioremediation processes due to its resistance to high concentrations of Pb²⁺, ability to grow until 24 h of exposure, and possession of a gene that indicates the existence of mechanisms associated with resistance to lead (Pb²⁺).
