Prodigiosin produced by Serratia marcescens inhibits expression of MMP-9 and survivin and promotes caspase-3 activation with induction of apoptosis in acute lymphoblastic leukaemia cells

Growth Kinetics of Prodigiosin (Food Color) Produced by Novel Serratia marcescens bhu prodig Under Submerged Fermentation (SMF)

Prodigiosin is a promising food color due to its antibacterial, antimalarial, antimycotic characteristics, immunomodulating, and antitumor activities. Novel prodigiosin producing strain isolated from sugarcane field soil of Banaras Hindu University, India, characterized as Serratia marcescens bhu prodig by 16 sRNA. The effect of carbon, nitrogen source, and physical parameters (pH and temperature) on pigment yield was studied. The highest amount of pigment produced, which was 800.95 ± 0.05 mg/L, was detected when sorbitol and peptone were used as nitrogen and carbon source with pH 7 at 30 °C. The optimized condition scale-up in a bioreactor with a working capacity of 3.0 L, gave maximum pigment yield of 825 ± 0.05 mg/L with µ (Maximum specific growth rate), Yp/x, which represents the product yield coefficient, and Yp/s, which signifies the specific product yield coefficient and productivity of 0.3/h, 0.62, 0.80, and 0.02 g/L/h, respectively, after 72 h of cultivation in submerged fermentation (SMF). The isolated pigment was characterized as prodigiosin by the analysis of spectral data and GC-MS. The mass spectrophotometry investigation characterized pigment as 4-methoxy-5(5 methyl-4-pentyl-2H-pyrrol-2-ylidene)- 2,2-bipyrrole ring structure. The GC-MS chromatogram showed m/z of 323, representing prodigiosin. The prodigiosin yield and productivity obtained in the current finding were higher than in previous reports.

Rise of the natural red pigment 'prodigiosin' as an immunomodulator in cancer

Cancer is a heterogeneous disease with multifaceted drug resistance mechanisms (e.g., tumour microenvironment [TME], tumour heterogeneity, and immune evasion). Natural products are interesting repository of bioactive molecules, especially those with anticancer activities. Prodigiosin, a red pigment produced by Serratia marcescens, possesses inherent anticancer characteristics, showing interesting antitumour activities in different cancers (e.g., breast, gastric) with low or without harmful effects on normal cells. The present review discusses the potential role of prodigiosin in modulating and reprogramming the metabolism of the various immune cells in the TME, such as T and B lymphocytes, tumour-associated macrophages (TAMs), natural killer (NK) cells, and tumour-associated dendritic cells (TADCs), and myeloid-derived suppressor cells (MDSCs) which in turn might introduce as an immunomodulator in cancer therapy.

Mechanisms underlying the inhibitory effects of Cd2+ on prodigiosin synthesis in Serratia marcescens KMR-3

Prodigiosin (2-methyl-3-pentyl-6-methoxyprodiginine), a red-colored microbial pigment, is produced in large quantities by Serratia marcescens KMR-3. This bacterium can grow in a medium with a Cd²⁺ concentration of 500 mg/L, but it does not produce prodigiosin when the Cd²⁺ concentration in the medium is higher than 140 mg/L. Therefore, we investigated the mechanisms by which Cd²⁺ inhibits prodigiosin synthesis. Upon addition of Cd²⁺ to the medium, the expression of the prodigiosin (pig) gene cluster was significantly downregulated. Simultaneously, genes encoding proteins related to the synthesis of arginine and proline(prodigiosin precursors) were significantly downregulated, while the degradation-related genes were upregulated. Furthermore, PigF, which encodes a key enzyme involved in the synthesis of 4-methoxy-2,2'-bipyrrole-5-carboxaldehyde and PigC, which encodes a key enzyme involved in the last step of prodigiosin synthesis, were downregulated by 80% and 55%, respectively, following Cd²⁺ treatment. As PigC and PigF are located on the cell membrane and are involved in the final steps of prodigiosin synthesis, the cell membrane might be presumed to be the site of prodigiosin synthesis. The bacterial membrane exhibited different degrees of elongation, folding, fragmentation, and sagging after the addition of Cd²⁺, while likely destroying the site of prodigiosin synthesis.

Characterization of prodigiosin pigment by Serratia marcescens and the evaluation of its bioactivities

The aim of the present study is to discover a bacterial pigment providing protection and prevention of neurological damage and cancer development, which can have a role as a non-synthetic food additive in the food industry as well as an active drug ingredient of anticancer drugs and pharmaceuticals for neural injury. Within this scope, Serratia marcescens MB703 strain was used to produce prodigiosin. Characterization of the prodigiosin was carried out using UV-VIS, and FT-IR. In addition, its inhibitory action on AChE and antioxidant activities were determined. The cytotoxic, genotoxic and antigenotoxic activities of the prodigiosin as well as its antiproliferative activities were detected. It was determined that the maximum production of the prodigiosin (72 mg/L). The prodigiosin was found to cause no significant difference in its inhibitory effect on AChE. The prodigiosin was found effective on all antioxidant parameters tested. The IC₅₀ values of the prodigiosin on SK-MEL-30 and HT-29 cells were calculated as 70 and 47 μM, respectively. This IC₅₀ values of the prodigiosin showed no cytotoxic effect on L929 cells. Prodigiosin did not have genotoxic effect alone and also seem to decrease DNA damage induced by H₂O₂ in L929 cells. The findings of in vitro experimental studies suggest that using the prodigiosin pigment as a drug candidate for cancer and neurodegenerative disease therapy is both effective and safe.

Spontaneous Regression of Blastic Plasmacytoid Dendritic Cell Neoplasm Following Sepsis by Serratia marcescens: A Case Report and Literature Review

Spontaneous regression is rare in patients with blastic plasmacytoid dendritic cell neoplasm (BPDCN). An 85-year-old man presented with pancytopenia and skin lesions, and the bone marrow exhibited 79.6% CD4+, CD56+, CD123+, and TCL-1+ abnormal cells, with a normal karyotype; he was thus diagnosed with BPDCN. While being followed without chemotherapy, he was admitted due to sepsis induced by Serratia marcescens, which was successfully treated with antibiotics. Notably, his blood cell counts improved, and the skin lesions disappeared. To our knowledge, this is the first reported case of spontaneous regression of BPDCN with a decrease in tumor cells in the bone marrow following sepsis.

Prodigiosin Sensitizes Sensitive and Resistant Urothelial Carcinoma Cells to Cisplatin Treatment

Cisplatin-based treatment is the standard of care therapy for urothelial carcinomas. However, complex cisplatin resistance mechanisms limit the success of this approach. Both apoptosis and autophagy have been shown to contribute to this resistance. Prodigiosin, a secondary metabolite from various bacteria, exerts different biological activities including the modulation of these two cellular stress response pathways. We analyzed the effect of prodigiosin on protein levels of different autophagy- and apoptosis-related proteins in cisplatin-sensitive and -resistant urothelial carcinoma cells (UCCs). Furthermore, we investigated the effect on cell viability of prodigiosin alone or in combination with cisplatin. We made use of four different pairs of cisplatin-sensitive and -resistant UCCs. We found that prodigiosin blocked autophagy in UCCs and re-sensitized cisplatin-resistant cells to apoptotic cell death. Furthermore, we found that prodigiosin is a potent anticancer agent with nanomolar IC50 values in all tested UCCs. In combination studies, we observed that prodigiosin sensitized both cisplatin-sensitive and -resistant urothelial carcinoma cell lines to cisplatin treatment with synergistic effects in most tested cell lines. These effects of prodigiosin are at least partially mediated by altering lysosomal function, since we detected reduced activities of cathepsin B and L. We propose that prodigiosin is a promising candidate for the therapy of cisplatin-resistant urothelial carcinomas, either as a single agent or in combinatory therapeutic approaches.

A two-step resin based approach to reveal survivin-selective fluorescent probes

The identification of modulators for proteins without assayable biochemical activity remains a challenge in chemical biology. The presented approach adapts a high-throughput fluorescence binding assay and functional chromatography, two protein-resin technologies, enabling the discovery and isolation of fluorescent natural product probes that target proteins independently of biochemical function. The resulting probes also suggest targetable pockets for lead discovery. Using human survivin as a model, we demonstrate this method with the discovery of members of the prodiginine family as fluorescent probes to the cancer target survivin.

Selective Cytotoxic Activity of Prodigiosin@halloysite Nanoformulation

Prodigiosin, a bioactive secondary metabolite produced by Serratia marcescens, is an effective proapoptotic agent against various cancer cell lines, with little or no toxicity toward normal cells. The hydrophobicity of prodigiosin limits its use for medical and biotechnological applications, these limitations, however, can be overcome by using nanoscale drug carriers, resulting in promising formulations for target delivery systems with great potential for anticancer therapy. Here we report on prodigiosin-loaded halloysite-based nanoformulation and its effects on viability of malignant and non-malignant cells. We have found that prodigiosin-loaded halloysite nanotubes inhibit human epithelial colorectal adenocarcinoma (Caco-2) and human colon carcinoma (HCT116) cells proliferative activity. After treatment of Caco-2 cells with prodigiosin-loaded halloysite nanotubes, we have observed a disorganization of the F-actin structure. Comparison of this effects on malignant (Caco-2, HCT116) and non-malignant (MSC, HSF) cells suggests the selective cytotoxic and genotoxic activity of prodigiosin-HNTs nanoformulation.

The protection effects of survivin in the cell model of CVB3-induced viral myocarditis

Viral myocarditis (VMC) is a widely studied but poorly understood inflammatory cardiomyopathy which mainly affects children and young adults and results in adverse outcomes. Cardiomyocyte apoptosis was reported important in the progress of coxsackievirus B3 (CVB3)-induced VMC and the blocking of this process may contribute to the therapeutic effect towards VMC. Therefore, this study was designed to explore whether survivin, one of the strongest antiapoptotic proteins, can protect cardiomyocytes from apoptosis in VMC and to discover its related mechanisms. Here, the cultured neonatal mouse cardiomyocytes (NMCs) were exposed to CVB3 to establish the cell model of VMC and the results of Western Blot showed that the protein expression of survivin in CVB3-infected NMCs varied at different post-infection time. Lentivirus was next used to examine the function of survivin in CVB3-infected NMCs. TUNEL assay demonstrated that the overexpression of survivin interrupted CVB3-induced apoptosis. It was next examined whether caspase-3 and -9 were involved in the antiapoptotic pathway initiated by survivin via Western Blot. The results showed a reverse relationship between the protein expression of survivin and that of cleaved caspase-3 and cleaved caspase-9, suggesting that survivin may attenuate apoptosis through restraining the activity of caspase-3 and -9. Moreover, the supernatant fluid of cultured NMCs was extracted to detect the quantitation of released lactate dehydrogenase (LDH) and a sharp decrease was discovered in the survivin-overexpressed group compared to the CVB3-infected group, indicating a protective role of survivin in the cell model of CVB3-induced myocarditis. This study demonstrated that survivin was triggered by CVB3 infection in NMCs and survivin executed its antiapoptotic effects via caspase-3- and caspase-9-dependent signaling pathway.

The production and bioactivity of prodigiosin: quo vadis?

Prodigiosin (PG), a red tripyrrole pigment, belongs to a member of the prodiginine family and is normally secreted by various sources including Serratia marcescens and other Gram-negative bacteria. The studies of PG have received innovative devotion as a result of reported antimicrobial, larvicidal and anti-nematoid immunomodulation and antitumor properties, owing to its antibiotic and cytotoxic activities. This review provides a comprehensive summary of research undertaken toward the isolation and structural elucidation of the prodiginine family of natural products. Additionally, the current evidence-based understanding of the biological activities and medicinal potential of PG is employed to determine the efficacy, with some reports of information related to pharmacokinetics, pharmacodynamics and toxicology.