-
The Journal of General and Applied... May 2024Proteolytic enzymes stand out as the most widely employed category utilized in manufacturing industry. A new protease was separated from Planococcus sp.11815 strain and...
Proteolytic enzymes stand out as the most widely employed category utilized in manufacturing industry. A new protease was separated from Planococcus sp.11815 strain and named as nprS-15615 in this research. The gene of this protease has not been reported, and its enzymatic properties have been studied for the first time. To enhance enzyme production, the Planococcus sp. protease gene was expressed in Bacillus licheniformis 2709. The expression level of nprS-15615 was observed under the control of regulatory elements P. nprS-15615 protease activity reached 1186.24±32.87 U/mL after 48 hours of cultivation in shake flasks which was nearly four times the output of the original bacteria (291.38±25.73U/mL). The optimum temperature and pH of the recombinant protease were 30 ℃ and 8.0, respectively.The enzyme exhibited the highest capacity for hydrolyzing casein and demonstrated resilience towards a NaCl concentration of 10.0% (wt/v). Furthermore, in the presence of 0.5% surfactants, the recombinant protease activity can maintain above 75%, and with the existence of 0.5% liquid detergents, there was basically no loss of enzyme activity which indicated that nprS-15615 had good compatibility with surfactants and liquid detergents. In addition, npS-15615 performed well in the washing experiment, and the washing effect at 20 ℃ can be significantly improved by adding crude enzyme solution in the washing process.
Topics: Detergents; Hydrogen-Ion Concentration; Temperature; Metalloproteases; Recombinant Proteins; Bacterial Proteins; Bacillus licheniformis; Enzyme Stability; Planococcus Bacteria; Caseins; Gene Expression; Cloning, Molecular; Surface-Active Agents; Hydrolysis
PubMed: 37880082
DOI: 10.2323/jgam.2023.09.002 -
International Journal of Systematic and... Feb 2024A Gram-staining-positive, motile, aerobic and rod-shaped bacterium, designated strain MA9 was isolated from wetland soil of ecology park, in Seoul, Republic of Korea....
A Gram-staining-positive, motile, aerobic and rod-shaped bacterium, designated strain MA9 was isolated from wetland soil of ecology park, in Seoul, Republic of Korea. This bacterium was characterized to determine its taxonomic position by using the polyphasic approach. Strain MA9 grew at 10-37 °C and at pH 6.0-9.5 on TSB. Menaquinone MK-7 was the predominant respiratory quinone and iso-C, iso-C and C c alcohol were the major fatty acids. The main polar lipids were phosphatidylethanolamine (PE), phosphatidylserine (PS), diphosphatidylglycerol (DPG) and phosphatidylglycerol (PG). The peptidoglycan type of the cell wall was A4α l-Lys-d-Glu. Based on 16S rRNA gene sequencing, strain MA9 clustered with species of the genus and appeared closely related to DSM 12223 (97.8 % sequence similarity), DSM 21993 (97.6 %), DSM 21046 (97.6 %) and DSM 101595 (96.6 %). The G+C content of the genomic DNA was 37.0 mol%. Digital DNA-DNA hybridization between strain MA9 and type strains of , , and resulted in values below 70 %. Strain MA9 could be differentiated genotypically and phenotypically from the recognized species of the genus . The isolate therefore represents a novel species, for which the name sp. nov. is proposed, with the type strain MA9 (=KACC 22212 = LMG 32188).
Topics: Fatty Acids; Soil; RNA, Ribosomal, 16S; Wetlands; Soil Microbiology; DNA, Bacterial; Base Composition; Phylogeny; Sequence Analysis, DNA; Bacterial Typing Techniques; Planococcaceae
PubMed: 38323635
DOI: 10.1099/ijsem.0.006065 -
Journal of Thermal Biology Feb 2024Heat stress is a common environmental factor in livestock breeding that has been shown to impact the development of antibiotic resistance within the gut microbiota of...
Heat stress is a common environmental factor in livestock breeding that has been shown to impact the development of antibiotic resistance within the gut microbiota of both human and animals. However, studies investigating the effect of temperature on antibiotic resistance in Enterococcus isolates remain limited. In this study, specific pathogen free (SPF) mice were divided into a control group maintained at normal temperature and an experimental group subjected to daily 1-h heat stress at 38 °C, respectively. Gene expression analysis was conducted to evaluate the activation of heat shock responsive genes in the liver of mice. Additionally, the antibiotic-resistant profile and antibiotic resistant genes (ARGs) in fecal samples from mice were analyzed. The results showed an upregulation of heat-inducible proteins HSP27, HSP70 and HSP90 following heat stress exposure, indicating successful induction of cellular stress within the mice. Furthermore, heat stress resulted in an increase in the proportion of erythromycin-resistant Enterococcus isolates, escalating from 0 % to 0.23 % over a 30-day duration of heat stress. The resistance of Enterococcus isolates to erythromycin also had a 128-fold increase in minimum inhibitory concentration (MIC) within the heated-stressed group compared to the control group. Additionally, a 2∼8-fold rise in chloramphenicol MIC was observed among these erythromycin-resistant Enterococcus isolates. The acquisition of ermB genes was predominantly responsible for mediating the erythromycin resistance in these Enterococcus isolates. Moreover, the abundance of macrolide, lincosamide and streptogramin (MLS) resistant-related genes in the fecal samples from the heat-stressed group exhibited a significant elevation compared to the control group, primarily driven by changes in bacterial community composition, especially Enterococcaceae and Planococcaceae, and the transfer of mobile genetic elements (MGEs), particularly insertion elements. Collectively, these results highlight the role of environmental heat stress in promoting antibiotic resistance in Enterococcus isolates and partly explain the increasing prevalence of erythromycin-resistant Enterococcus isolates observed among animals in recent years.
Topics: Humans; Animals; Mice; Erythromycin; Enterococcus; Anti-Bacterial Agents; Feces; Heat-Shock Response
PubMed: 38428103
DOI: 10.1016/j.jtherbio.2024.103786 -
Journal of Environmental Management May 2024The microbially induced calcium carbonate precipitation (MICP) technology is an emerging novel and sustainable technique for soil stabilization and remediation. MICP, a...
The microbially induced calcium carbonate precipitation (MICP) technology is an emerging novel and sustainable technique for soil stabilization and remediation. MICP, a microorganism-mediated biomineralization process, has attracted interest for its potential to enhance soil characteristics. The inclusion of biochar, a carbon-rich substance formed by biomass pyrolysis, adds another degree of intricacy to this process. The study highlights the impact of the combination of biochar and MICP together, using a bacterium, Sporosarcina ureae, on soil improvement. This blend of MICP and biochar improved the soil in terms of its geotechnical properties and also enabled the sequestering of carbon safely. It was observed that addition of 4% biochar significantly increased the soil's shear strength parameters (c and φ) as well as its stiffness after 21 treatment cycles. This improvement was because the calcium carbonate precipitate, which acts as a crucial binding agent, increased significantly due to microbial action in the soil-biochar mixture compared to the pure soil sample. The excess carbonate precipitation on account of biochar addition was verified through SEM-EDAX analysis where the images showed noteworthy carbonate precipitation on the surface of particles and increment in the calcium mass at the same treatment cycles when compared with untreated sand. The collaboration between MICP and biochar effectively increased the carbon sequestration within the sand sample. It was observed that at 21 cycles of treatment, the carbon storage within the sand sample increased by almost 3 times at 4% biochar compared to sand without any biochar. The statistical analysis further affirmed that strength depends on both biochar and the number of treatment cycles, whereas carbon sequestration potential is primarily influenced by the biochar content alone. This strategy, as a sustainable and environmentally friendly approach, has the potential to reform soil improvement practices and contribute to both soil strength enhancement and climate change mitigation, supporting the maintenance of ecological balance.
Topics: Calcium Carbonate; Charcoal; Sporosarcina; Soil; Sand
PubMed: 38723498
DOI: 10.1016/j.jenvman.2024.121048 -
International Journal of Systematic and... Mar 2024A novel bacterial strain, APC 4016, was previously isolated from the skin of a snub-nosed spiny eel, , from a depth of 1000 m in the northern Atlantic Ocean. Cells...
A novel bacterial strain, APC 4016, was previously isolated from the skin of a snub-nosed spiny eel, , from a depth of 1000 m in the northern Atlantic Ocean. Cells were aerobic, cocci, motile, Gram-positive to Gram-variable staining, and gave rise to orange-pigmented colonies. Growth occurred at 4-40 °C (optimum, 25-28 °C), pH 5.5-12 (optimum, pH 7-7.5), and 0-12 % (w/v) NaCl (optimum, 1 %). 16S rRNA gene phylogenetic analysis confirmed that strain APC 4016 belonged to the genus and was most closely related to IFO 12536 (98.98 % 16S similarity). However, digital DNA-DNA hybridization and average nucleotide identity values between these two strains were low, at 20.1 and 83.8 %, respectively. Major (>10 %) cellular fatty acids of strain APC 4016 were iso-C, anteiso-C and C-ω-Alc. The predominant respiratory quinones were menaquinones 5, 6, 7 and 8. The major cellular polar lipids were phosphatidylglycerol, diphosphatidylglycerol and phosphatidylethanolamine, and three unknown lipids were also present. The draft genome sequence is 3.6 Mb with a G+C content of 45.25 mol%. This strain was previously shown to have antimicrobial activity and to encode bacteriocin and secondary metabolite biosynthetic gene clusters. Based on the phylogenetic analysis and its distinct phenotypic characteristics, strain APC 4016 is deemed to represent a novel species of the genus , and for which the name sp. nov. is proposed. The type strain of this species is APC 4016 (=DSM 115753=NCIMB 15463).
Topics: Animals; Fatty Acids; Phospholipids; Phylogeny; RNA, Ribosomal, 16S; Sequence Analysis, DNA; Base Composition; Bacterial Typing Techniques; DNA, Bacterial; Planococcus Bacteria; Eels
PubMed: 38512752
DOI: 10.1099/ijsem.0.006298 -
Journal of Applied Microbiology Jan 2024This study aimed to understand the morphological effects of (in)organic additives on microbially induced calcium carbonate precipitation (MICP).
AIM
This study aimed to understand the morphological effects of (in)organic additives on microbially induced calcium carbonate precipitation (MICP).
METHODS AND RESULTS
MICP was monitored in real time in the presence of (in)organic additives: bovine serum albumin (BSA), biofilm surface layer protein A (BslA), magnesium chloride (MgCl2), and poly-l-lysine. This monitoring was carried out using confocal microscopy to observe the formation of CaCO3 from the point of nucleation, in comparison to conditions without additives. Complementary methodologies, namely scanning electron microscopy, energy-dispersive X-ray spectroscopy and X-ray diffraction, were employed to assess the visual morphology, elemental composition, and crystalline structures of CaCO3, respectively, following the crystals' formation. The results demonstrated that in the presence of additives, more CaCO3 crystals were produced at 100 min compared to the reaction without additives. The inclusion of BslA resulted in larger crystals than reactions containing other additives, including MgCl2. BSA induced a significant number of crystals from the early stages of the reaction (20 min) but did not have a substantial impact on crystal size compared to conditions without additives. All additives led to a higher content of calcite compared to vaterite after a 24-h reaction, with the exception of MgCl2, which produced a substantial quantity of magnesium calcite.
CONCLUSIONS
The work demonstrates the effect of several (in)organic additives on MICP and sets the stage for further research to understand additive effects on MICP to achieve controlled CaCO3 precipitation.
Topics: Calcium Carbonate; Magnesium Chloride; Sporosarcina; Chemical Precipitation; Microscopy, Electron, Scanning
PubMed: 38111211
DOI: 10.1093/jambio/lxad309 -
Nucleic Acids Research Apr 2024RNA ligases are important enzymes in molecular biology and are highly useful for the manipulation and analysis of nucleic acids, including adapter ligation in...
RNA ligases are important enzymes in molecular biology and are highly useful for the manipulation and analysis of nucleic acids, including adapter ligation in next-generation sequencing of microRNAs. Thermophilic RNA ligases belonging to the RNA ligase 3 family are gaining attention for their use in molecular biology, for example a thermophilic RNA ligase from Methanobacterium thermoautotrophicum is commercially available for the adenylation of nucleic acids. Here we extensively characterise a newly identified RNA ligase from the thermophilic archaeon Palaeococcus pacificus (PpaRnl). PpaRnl exhibited significant substrate adenylation activity but low ligation activity across a range of oligonucleotide substrates. Mutation of Lys92 in motif I to alanine, resulted in an enzyme that lacked adenylation activity, but demonstrated improved ligation activity with pre-adenylated substrates (ATP-independent ligation). Subsequent structural characterisation revealed that in this mutant enzyme Lys238 was found in two alternate positions for coordination of the phosphate tail of ATP. In contrast mutation of Lys238 in motif V to glycine via structure-guided engineering enhanced ATP-dependent ligation activity via an arginine residue compensating for the absence of Lys238. Ligation activity for both mutations was higher than the wild-type, with activity observed across a range of oligonucleotide substrates with varying sequence and secondary structure.
Topics: RNA Ligase (ATP); Substrate Specificity; Archaeal Proteins; Planococcaceae; Protein Engineering; Mutation; Models, Molecular; Adenosine Triphosphate; Oligonucleotides
PubMed: 38421610
DOI: 10.1093/nar/gkae149 -
ACS Applied Materials & Interfaces Jan 2024Microbially induced calcium carbonate precipitation (MICP) has emerged as a novel technology with the potential to produce building materials through lower-temperature...
Microbially induced calcium carbonate precipitation (MICP) has emerged as a novel technology with the potential to produce building materials through lower-temperature processes. The formation of calcium carbonate bridges in MICP allows the biocementation of aggregate particles to produce biobricks. Current approaches require several pulses of microbes and mineralization media to increase the quantity of calcium carbonate minerals and improve the strength of the material, thus leading to a reduction in sustainability. One potential technique to improve the efficiency of strength development involves trapping the bacteria on the aggregate surfaces using silane coupling agents such as positively charged 3-aminopropyl-methyl-diethoxysilane (APMDES). This treatment traps bacteria on sand through electrostatic interactions that attract negatively charged walls of bacteria to positively charged amine groups. The APMDES treatment promoted an abundant and immediate association of bacteria with sand, increasing the spatial density of ureolytic microbes on sand and promoting efficient initial calcium carbonate precipitation. Though microbial viability was compromised by treatment, urea hydrolysis was minimally affected. Strength was gained much more rapidly for the APMDES-treated sand than for the untreated sand. Three injections of bacteria and biomineralization media using APMDES-treated sand led to the same strength gain as seven injections using untreated sand. The higher strength with APMDES treatment was not explained by increased calcium carbonate accrual in the structure and may be influenced by additional factors such as differences in the microstructure of calcium carbonate bridges between sand particles. Overall, incorporating pretreatment methods, such as amine silane coupling agents, opens a new avenue in biomineralization research by producing materials with an improved efficiency and sustainability.
Topics: Sand; Silanes; Sporosarcina; Bacteria; Carbonates; Calcium Carbonate; Amines; Chemical Precipitation
PubMed: 38176018
DOI: 10.1021/acsami.3c13971 -
Microbial Ecology May 2024Biocrust inoculation and microbially induced carbonate precipitation (MICP) are tools used in restoring degraded arid lands. It remains unclear whether the ecological...
Biocrust inoculation and microbially induced carbonate precipitation (MICP) are tools used in restoring degraded arid lands. It remains unclear whether the ecological functions of the two tools persist when these methods are combined and subjected to freeze-thaw (FT) cycles. We hypothesized a synergetic interaction between MICP treatment and biocrust under FT cycles, which would allow both components to retain their ecological functions. We grew cyanobacterial (Nostoc commune) biocrusts on bare soil and on MICP (Sporosarcina pasteurii)-treated soil, subjecting them to repeated FT cycles simulating the Mongolian climate. Generalized linear modeling revealed that FT cycling did not affect physical structure or related functions but could increase the productivity and reduce the nutrient condition of the crust. The results confirm the high tolerance of MICP-treated soil and biocrust to FT cycling. MICP treatment + biocrust maintained higher total carbohydrate content under FT stress. Our study indicates that biocrust on biomineralized soil has a robust enough structure to endure FT cycling during spring and autumn and to promote restoration of degraded lands.
Topics: Soil Microbiology; Soil; Freezing; Cyanobacteria; Carbonates; Ecosystem; Sporosarcina
PubMed: 38730059
DOI: 10.1007/s00248-024-02389-w -
Journal of Environmental Management Oct 2023With the recent increases in energy demands, the dust hazards of coal mining caused by transportation, loading and unloading and other processes are becoming...
With the recent increases in energy demands, the dust hazards of coal mining caused by transportation, loading and unloading and other processes are becoming increasingly serious. To control dust in open pit coal mines more environmentally friendly and efficiently, and to promote the use and development of non-in situ high-yield urease microorganisms for dust suppression in coal mines, Bacillus pasteurii was selected for dust suppression experiments in this article. Additionally, the growth of microorganisms in the coal dust microenvironment was simulated, and the effect of microbial mineralization products on the calorific value of upper coal dust was further studied. Our findings indicated that Bacillus pasteurii induced dust suppression by forming a calcite precipitate with non-uniform particle size to coal dust cementation. Moreover, after a single spray, the wind erosion resistance efficiency was 84% when the wind speed was set at 10 m/s. The growth of microorganisms and urease activity in the coal dust leachate were largely equal to those in the control group, reaching a peak at approximately 24 h, that the maximum growth quantity of OD was about 1.5, and the maximum urease activity was 11 mmol·L·min. The difference between the peak heat release rate of mixed coal dust and pure coal was only 4.82 kW/m, which would not affect the value of coal products. Non in-situ Bacillus pasteurii can be growth metabolized normally in the microenvironment of coal dust. Finally, the mechanism of coal dust suppression by mineralization of microbial bacterial solution to form calcium carbonate was described by a reaction equation, which is important for further application and development of microbial dust suppressants.
Topics: Dust; Urease; Sporosarcina; Calcium Carbonate; Minerals; Coal; Coal Mining
PubMed: 37229857
DOI: 10.1016/j.jenvman.2023.118181