Abstract The clustered regularly interspaced short palindromic repeat (CRISPR)-Cas system mediates adaptive immunity against foreign nucleic acids in prokaryotes. However, efficient adaptation of a native CRISPR to purified viruses has only been observed for the type II-A from Streptococcus thermophilus industry strain, and rarely reported laboratory strains. Here, we provide second showing adaptation. Infected by newly isolated virus HHPV-2, Haloarcula hispanica I-B acquired spacers...

Small RNAs guard CRISPR-Cas The microbial adaptive immunity system benefits microbes by warding off genetic invaders, but it also inflicts a fitness cost because of occasional autoimmune reactions, rendering CRISPR loci evolutionarily unstable. Li et al. identified previously unnoticed toxin-antitoxin RNA pairs embedded within diverse loci. antitoxin mimics and repurposes the effector to transcriptionally repress toxin that would otherwise arrest cell growth sequestering rare transfer RNA....

Haloferax mediterranei is able to accumulate the bioplastic poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) with more than 10 mol% 3-hydroxyvalerate (3HV) from unrelated carbon sources. However, pathways that produce propionyl coenzyme A (propionyl-CoA), an important precursor of 3HV monomer, have not yet been determined. Bioinformatic analysis H. genome indicated this strain uses multiple for propionyl-CoA biosynthesis, including citramalate/2-oxobutyrate pathway,...

We report the biosynthesis of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) random copolymers (R-PHBV) or higher-order (O-PHBV) in Haloferax mediterranei, with adjustable 3-hydroxyvalerate (3HV) incorporation by cofeeding valerate glucose. Their microchemical structure, molecular weight and its distribution, thermal mechanical properties were characterized NMR, GPC, DSC, TGA, universal testing machine, respectively. 13C NMR studies showed that O-PHBV consisted short segments PHB PHV...

Type I CRISPR-Cas systems are widespread and have exhibited high versatility efficiency in genome editing gene regulation prokaryotes. However, due to the multi-subunit composition large size, their application eukaryotes has not been thoroughly investigated. Here, we demonstrate that type I-F2 Cascade, most compact among systems, with a total size smaller than of SpCas9, can be developed for transcriptional activation human cells. The engineered tool match or surpass dCas9. Additionally,...

Polyhydroxyalkanoates (PHAs) are synthesized and assembled as PHA granules that undergo well-regulated formation in many microorganisms. However, this regulation remains unclear haloarchaea. In study, we identified a granule-associated regulator (PhaR) negatively regulates the expression of both its own gene granule structural phaP same operon (phaRP) Haloferax mediterranei. Chromatin immunoprecipitation-quantitative PCR (ChIP-qPCR) assays demonstrated significant interaction between PhaR...

Lycopene attracts increasing interests in the pharmaceutical, food, and cosmetic industries due to its anti-oxidative anti-cancer properties. Compared with other lycopene production methods, such as chemical synthesis or direct extraction from plants, biosynthesis approach using microbes is more economical sustainable. In this work, we engineered Haloferax mediterranei, a halophilic archaeon, new producer. H. mediterranei has de novo synthetic pathway for but cannot accumulate compound. To...

Soda-saline lakes are a special type of alkaline lake in which the chloride concentration is greater than carbonate/bicarbonate concentration. Due to high pH and usually higher osmotic pressure that normal soda lake, microbes may need more energy thrive such double-extreme environment. In this study, we systematically investigated microbiome brine sediment samples nine artificially separated ponds (salinities from 5.5% saturation) within two soda-saline Inner Mongolia China, assisted by deep...

The surface structures of archaeal cells, many which exist at high temperatures, salinity, and non-physiological pH, are key factors for their adaptation to extreme living conditions. In the haloarchaeon Haloarcula hispanica, we have discovered a thin filamentous appendage called tat-fimbriae ("tafi"), were identified be composed three protein subunits, TafA, TafC, TafE, among TafA is major fimbrial subunit. Molecular genetic evidence demonstrates was transported through twin-arginine...

The adaptive immune system comprising CRISPR (clustered regularly interspaced short palindromic repeats) arrays and cas (CRISPR-associated) genes has been discovered in a wide range of bacteria archaea recently attracted comprehensive investigations. However, the subtype I-B CRISPR-Cas haloarchaea less characterized. Here, we investigated Cas6-mediated RNA processing Haloferax mediterranei. Cas6 cleavage site, as well transcription start was experimentally determined, transcripts detected...

Abstract The origin of methanogenesis can be traced to the common ancestor non-DPANN archaea, whereas haloarchaea (or Halobacteria) are believed have evolved from a methanogenic through multiple evolutionary events. However, due accelerated evolution and compositional bias proteins adapting hypersaline habitats, Halobacteria exhibit substantial divergence methanogens, identification closest methanogen (either Methanonatronarchaeia or other taxa) remains subject debate. Here, we obtained five...

Cellulolytic microorganisms play a crucial role in agricultural waste disposal. Strain QXD-8T was isolated from soil northern China. Similarity analyses of the 16S rRNA gene, as well 120 conserved genes whole-genome sequence, indicate that it represents novel species within genus Microbacterium. The Microbacterium sp. able to grow on CAM plate with sodium carboxymethyl cellulose carbon source at 15 °C, forming transparent hydrolysis circle after Congo red staining, even though optimal...

Abstract Although polyhydroxyalkanoate (PHA) accumulation and mobilization are one of the most general mechanisms for haloarchaea to adapt hypersaline environments with changeable carbon sources, PHA pathways still not clear any haloarchaea. In this study, functions five putative ( R )-specific enoyl-CoA hydratases (R-ECHs) in Haloferax mediterranei , named PhaJ1 PhaJ5, respectively, were thoroughly investigated. Through gene deletion complementation, we demonstrated that only certain these...

The key enzymes and pathways involved in polyhydroxyalkanoate (PHA) biosynthesis haloarchaea have been identified recent years, but the haloarchaeal for PHA degradation remain unknown. In this study, a patatin-like depolymerase, PhaZh1, was determined to be located on granules haloarchaeon Haloferax mediterranei. PhaZh1 hydrolyzed native (nPHA) [including polyhydroxybutyrate (nPHB) poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (nPHBV) study] vitro with 3-hydroxybutyrate (3HB) monomer as...

The KTK 4A-related Thermoplasmata thrives in the sediment of saline lakes; however, systematic research on its taxonomy, environmental adaptation and metabolism is lacking. Here, we detected this abundant lineage five artificially separated ponds (salinity 7.0%-33.0%) within a Chinese soda-saline lake using culture-independent metagenomics archaeal 16S rRNA gene amplicons. phylogenies based gene, 122 ubiquitous single-copy proteins genome-level identity analyses among metagenome-assembled...

Phosphoenolpyruvate (PEP)/pyruvate interconversion is a major metabolic point in glycolysis and gluconeogenesis catalyzed by various sets of enzymes different Archaea groups. In this study, we report the key that catalyze anabolic catabolic directions PEP/pyruvate Haloferax mediterranei The silico analysis showed presence potassium-dependent pyruvate kinase (PYKHm [HFX_0773]) two phosphoenol synthetase (PPS) candidates (PPSHm [HFX_0782] PPS homolog protein named PPS-like [HFX_2676]) strain....

The key enzymes for poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) biosynthesis in haloarchaea have been identified except the β-ketothiolase(s), which condense two acetyl coenzyme A (acetyl-CoA) molecules to acetoacetyl-CoA, or one acetyl-CoA and propionyl-CoA 3-ketovaleryl-CoA. Whole-genome analysis has revealed eight potential β-ketothiolase genes haloarchaeon Haloferax mediterranei, among PHBV-specific BktB PhaA were by gene knockout complementation analysis. Unlike all known...

Lysine acetylation is a reversible and highly regulated post-translational modification that plays critical role in regulating many aspects of cellular processes, both bacteria eukaryotes. However, this has not been systematically studied archaea. Herein, we report the lysine acetylome model haloarchaeon, Haloferax mediterranei. Using immunoaffinity enrichment LC–MS/MS analysis, identified 1017 sites 643 proteins, accounting for 17.3% total proteins haloarchaeon. Bioinformatics analysis...