Saccharopolyspora mangrovi sp. nov., a novel mangrove soil actinobacterium with distinct metabolic potential revealed by comparative genomic analysis.

A novel mangrove soil-derived actinomycete, strain S2-29T, was found to be most closely related to Saccharopolyspora karakumensis 5K548T based on 16 S rRNA sequence (99.24% similarity) and genomic phylogenetic analyses. However, significant divergence in digital DNA-DNA hybridization, average nucleotide identity, and unique biosynthetic gene cluster possession distinguished S2-29T as a distinct Saccharopolyspora species. Pan genome evaluation revealed exceptional genomic flexibility in genus Saccharopolyspora, with > 95% accessory genome content. Strain S2-29T harbored 718 unique genes, largely implicated in energetic metabolisms, indicating different metabolic capacities from its close relatives. Several uncharacterized biosynthetic gene clusters in strain S2-29T highlighted the strain's untapped capacity to produce novel functional compounds with potential biotechnological applications. Designation as novel species Saccharopolyspora mangrovi sp. nov. (type strain S2-29T = JCM 34,548T = CGMCC 4.7716T) was warranted, expanding the known Saccharopolyspora diversity and ecology. The discovery of this mangrove-adapted strain advances understanding of the genus while highlighting an untapped source of chemical diversity.

Unveiling the role of HP1α-HDAC1-STAT1 axis as a therapeutic target for HP1α-positive intrahepatic cholangiocarcinoma.

BACKGROUND: Intrahepatic cholangiocarcinoma (ICCA) is a heterogeneous group of malignant tumors characterized by high recurrence rate and poor prognosis. Heterochromatin Protein 1α (HP1α) is one of the most important nonhistone chromosomal proteins involved in transcriptional silencing via heterochromatin formation and structural maintenance. The effect of HP1α on the progression of ICCA remained unclear. METHODS: The effect on the proliferation of ICCA was detected by experiments in two cell lines and two ICCA mouse models. The interaction between HP1α and Histone Deacetylase 1 (HDAC1) was determined using Electrospray Ionization Mass Spectrometry (ESI-MS) and the binding mechanism was studied using immunoprecipitation assays (co-IP). The target gene was screened out by RNA sequencing (RNA-seq). The occupation of DNA binding proteins and histone modifications were predicted by bioinformatic methods and evaluated by Cleavage Under Targets and Tagmentation (CUT & Tag) and Chromatin immunoprecipitation (ChIP). RESULTS: HP1α was upregulated in intrahepatic cholangiocarcinoma (ICCA) tissues and regulated the proliferation of ICCA cells by inhibiting the interferon pathway in a Signal Transducer and Activator of Transcription 1 (STAT1)-dependent manner. Mechanistically, STAT1 is transcriptionally regulated by the HP1α-HDAC1 complex directly and epigenetically via promoter binding and changes in different histone modifications, as validated by high-throughput sequencing. Broad-spectrum HDAC inhibitor (HDACi) activates the interferon pathway and inhibits the proliferation of ICCA cells by downregulating HP1α and targeting the heterodimer. Broad-spectrum HDACi plus interferon preparation regimen was found to improve the antiproliferative effects and delay ICCA development in vivo and in vitro, which took advantage of basal activation as well as direct activation of the interferon pathway. HP1α participates in mediating the cellular resistance to both agents. CONCLUSIONS: HP1α-HDAC1 complex influences interferon pathway activation by directly and epigenetically regulating STAT1 in transcriptional level. The broad-spectrum HDACi plus interferon preparation regimen inhibits ICCA development, providing feasible strategies for ICCA treatment. Targeting the HP1α-HDAC1-STAT1 axis is a possible strategy for treating ICCA, especially HP1α-positive cases.

Chemical structure, properties and potential applications of surfactin, as well as advanced strategies for improving its microbial production.

Surfactin, a cyclic lipopeptide produced by microbes belonging to the genus Bacillus, is one of the most effective biosurfactants available in many industrial fields. However, its low production and high cost have intensively constrained its commercial applications. In this review, we first summarize the molecular structure, biological properties, beneficial roles and potential applications of surfactin in the fields of medical care and food safety, highlighting the great medical and commercial values of making its industrial production into reality. Further, genetic regulation for surfactin biosynthesis and advanced strategies for enhancing its microbial production, including optimizing fermentation conditions, rational genetic engineering and synthetic biology combined with metabolic engineering approaches, are elucidated. Finally, prospects for improving surfactin biosynthesis are discussed, and the establishment of suitable chassis hosts for exogenous production of surfactin might serve as an important strategy in future research.

Streptomonospora mangrovi sp. nov., isolated from mangrove soil showing similar metabolic capabilities, but distinct secondary metabolites profiles.

A novel actinomycete, designated strain S1-112 T, was isolated from a mangrove soil sample from Hainan, China, and characterized using a polyphasic approach. Strain S1-112 T showed the highest similarity of the 16S rRNA gene to Streptomonospora nanhaiensis 12A09T (99.24%). Their close relationship was further supported by phylogenetic analyses, which placed these two strains within a stable clade. The highest values of digital DNA-DNA hybridization (dDDH, 41.4%) and average nucleotide identity (ANI, 90.55%) were detected between strain S1-112 T and Streptomonospora halotolerans NEAU-Jh2-17 T. Genotypic and phenotypic characteristics demonstrated that strain S1-112 T could be distinguished from its closely related relatives. We also profiled the pan-genome and metabolic features of genomic assemblies of strains belonging to the genus Streptomonospora, indicating similar functional capacities and metabolic activities. However, all of these strains showed promising potential for producing diverse types of secondary metabolites. In conclusion, strain S1-112 T represents a novel species of the genus Streptomonospora, for which the name Streptomonospora mangrovi sp. nov. was proposed. The type strain is S1-112 T (= JCM 34292 T).

Young thoracic vertebra diffuse idiopathic skeletal hyperostosis with Scheuermann disease: A case report.

BACKGROUND: Diffuse idiopathic skeletal hyperostosis (DISH) is a disorder characterised by the calcification and ossification of ligaments and entheses. It is a frequent occurrence in elderly males, but rarely encountered in younger individuals. CASE SUMMARY: A 24-year-old male was admitted to the hospital due to low back pain accompanied with numbness in both lower limbs for 10 d. Upon clinical examination and imaging tests, the patient was diagnosed with DISH with Scheuermann disease and thoracic spinal stenosis. Before the operation and medical treatment, the patient had hypoesthesia of the skin below the xiphoid process. Afterward, a standard laminectomy was conducted using ultrasonic bone curette and internal fixation was applied. Subsequently, the patient was given corticosteroids, neurotrophic drugs, hyperbaric oxygen and electric stimulation. As a result of the treatment, the patient's sensory level decreased to the navel level and there was no major change in the muscle strength of the lower limbs. During follow-up, the patient's skin sensation has returned to normal. CONCLUSION: This case is a rare instance of DISH co-existing with Scheuermann's disease in a young adult. This provides a valuable reference point for spine surgeons, as DISH is more commonly observed in middle-aged and elder adults.

Direct and indirect effects of IFN-α2b in malignancy treatment: not only an archer but also an arrow.

Interferon-α2b (IFN-α2b) is a highly active cytokine that belongs to the interferon-α (IFN-α) family. IFN-α2b has beneficial antiviral, antitumour, antiparasitic and immunomodulatory activities. Direct and indirect antiproliferative effects of IFN-α2b have been found to occur via multiple pathways, mainly the JAK-STAT pathway, in certain cancers. This article reviews mechanistic studies and clinical trials on IFN-α2b. Potential regulators of the function of IFN-α2b were also reviewed, which could be utilized to relieve the poor response to IFN-α2b. IFN-α2b can function not only by enhancing the systematic immune response but also by directly killing tumour cells. Different parts of JAK-STAT pathway activated by IFN-α2b, such as interferon alpha and beta receptors (IFNARs), Janus kinases (JAKs) and IFN-stimulated gene factor 3 (ISGF3), might serve as potential target for enhancing the pharmacological action of IFN-α2b. Despite some issues that remain to be solved, based on current evidence, IFN-α2b can inhibit disease progression and improve the survival of patients with certain types of malignant tumours. More efforts should be made to address potential adverse effects and complications.

Pseudonocardia humida sp. nov., an Actinomycete Isolated from Mangrove Soil Showing Distinct Distribution Pattern of Biosynthetic Gene Clusters.

A novel actinomycete strain, designated S2-4T, was isolated from a mangrove soil sample, and a polyphasic approach was employed to determine its taxonomic position. Phylogenetic analysis based on 16S rRNA gene indicated that strain S2-4T formed a unique clade next to that harboring Pseudonocardia dioxanivorans CB1190T, which shared the highest sequence similarity (98.20%) with the new isolate. Phylogenetic analysis based on core genes of genomic sequences displayed a different scenario, exhibiting closer phylogenetic relationship of strain S2-4T with several species with 16S rRNA gene sequence similarities ranging from 96.95 to 98.06%, which was confirmed by the phylogenetic tree reconstructed based on genomic sequences. Further, substantial differences between the genotypic properties of strain S2-4T and its closest neighbors, including digital DNA-DNA hybridization, average nucleotide identity, and distribution patterns of biosynthetic gene clusters (BGC), indicated the taxonomic position of strain S2-4T as a novel species of the genus Pseudonocardia. Accordingly, strain S2-4T was observed to show a different distribution pattern of a predicted BGC encoding ectoine by comparative genomic analysis, which could be strongly linked to its unique habitat distinct from where its close neighbors were isolated. The major cellular fatty acids were iso-C15:0, C21:0, and iso-C16:0. The predominant menaquinone was MK-8(H4). The polar lipids were composed of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidyl-N-monomethylethanolamine, phosphatidylcholine, phosphatidylinositol, phosphatidylinositol mannosides, and two unidentified glycolipids. Here, we propose a novel species of the genus Pseudonocardia: Pseudonocardia humida sp. nov. with the type strain S2-4T (= JCM 34291T = CGMCC 4.7706T).

Steroidobacter gossypii sp. nov., isolated from cotton field soil.

A Gram-negative bacterium, designated S1-65T, was isolated from soil samples collected from a cotton field located in the Xinjiang region of PR China. Results of 16S rRNA gene sequence analysis revealed that strain S1-65T was affiliated to the genus Steroidobacter with its closest phylogenetic relatives being 'Steroidobacter cummioxidans' 35Y (98.4 %), 'Steroidobacter agaridevorans' SA29-B (98.3 %) and Steroidobacter agariperforans KA5-BT (98.3 %). 16S rRNA-directed phylogenetic analysis showed that strain S1-65T formed a unique phylogenetic subclade next to 'S. agaridevorans' SA29-B and S. agariperforans KA5-BT, suggesting that strain S1-65T should be identified as a member of the genus Steroidobacter. Further, substantial differences between the genotypic properties of strain S1-65T and the members of the genus Steroidobacter, including average nucleotide identity and digital DNA-DNA hybridization, resolved the taxonomic position of strain S1-65T and suggested its positioning as representing a novel species of the genus Steroidobacter. The DNA G+C content of strain S1-65T was 62.5 mol%, based on its draft genome sequence. The predominant respiratory quinone was ubiquinone-8. The main fatty acids were identified as summed feature 3 (C16:1ω6c/C16:1ω7c), C16 : 0 and iso-C15 : 0. In addition, its polar lipid profile was composed of aminophospholipid, diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylglycerol. Here, we propose a novel species of the genus Steroidobacter: Steroidobacter gossypii sp. nov. with the type strain S1-65T (=JCM 34287T=CGMCC 1.18736T).

Genomic molecular signatures determined characterization of Mycolicibacterium gossypii sp. nov., a fast-growing mycobacterial species isolated from cotton field soil.

A Gram-positive, acid-fast and rapidly growing rod, designated S2-37 T, that could form yellowish colonies was isolated from one soil sample collected from cotton cropping field located in the Xinjiang region of China. Genomic analyses indicated that strain S2-37 T harbored T7SS secretion system and was very likely able to produce mycolic acid, which were typical features of pathogenetic mycobacterial species. 16S rRNA-directed phylogenetic analysis referred that strain S2-37 T was closely related to bacterial species belonging to the genus Mycolicibacterium, which was further confirmed by pan-genome phylogenetic analysis. Digital DNA-DNA hybridization and the average nucleotide identity presented that strain S2-37 T displayed the highest values of 39.1% (35.7-42.6%) and 81.28% with M. litorale CGMCC 4.5724 T, respectively. And characterization of conserved molecular signatures further supported the taxonomic position of strain S2-37 T belonging to the genus Mycolicibacterium. The main fatty acids were identified as C16:0, C18:0, C20:3ω3 and C22:6ω3. In addition, polar lipids profile was mainly composed of diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylinositol. Phylogenetic analyses, distinct fatty aids and antimicrobial resistance profiles indicated that strain S2-37 T represented genetically and phenotypically distinct from its closest phylogenetic neighbour, M. litorale CGMCC 4.5724 T. Here, we propose a novel species of the genus Mycolicibacterium: Mycolicibacterium gossypii sp. nov. with the type strain S2-37 T (= JCM 34327 T = CGMCC 1.18817 T).

Biotechnological production of lipid and terpenoid from thraustochytrids.

As fungus-like protists, thraustochytrids have been increasingly studied for their faster growth rates and high lipid content. In the 1990s, thraustochytrids were used as docosahexaenoic acid (DHA) producers for the first time. Thraustochytrids genera, such as Thraustochytrium, Schizochytrium, and Aurantiochytrium have been developed and patented as industrial strains for DHA production. The high DHA yield is attributed to its unique and efficient polyketide-like synthase (PKS) pathway. Moreover, thraustochytrids possess a completed mevalonate (MVA) pathway, so it can be used as host for terpenoid production. In order to improve strain performance, the metabolic engineering strategies have been applied to promote or disrupt intracellular metabolic pathways, such as genetic engineering and addition of chemical activators. However, it is difficult to realize industrialization only by improving strain performance. Various operation strategies were developed to enlarge the production quantities from the laboratory-scale, including two-stage cultivation strategies, scale-up technologies and bioreactor design. Moreover, an economical and effective downstream process is also an important consideration for the industrial application of thraustochytrids. Downstream costs accounts for 20-60% of the overall process costs, which represents an attractive target for increasing the cost-competitiveness of thraustochytrids, including how to improve the efficiency of lipid extraction and the further application of biomass residues. This review aims to overview the whole lipid biotechnology of thraustochytrids to provide the background information for researchers.