Bacterial Forms Research Articles

Shielding properties of the kombucha-derived bacterial cellulose

AbstractLiving organisms are constantly exposed to cosmic, terrestrial, and internal sources of radiation. As a result, they have developed natural radioprotective mechanisms. However, in some cases, these mechanisms may not be sufficient. Elevated doses and prolonged exposure to radiation, such as during radiotherapy or in extreme environments like spaceflight, can cause damage to DNA and increase the abundance of reactive oxygen species, which can affect biological processes. In contrast to synthetic ingredients, naturally produced radioprotective materials have good biocompatibility and are easy to recycle. This work investigates the radioprotective properties of the hydrogel biofilm produced by the kombucha microbial consortium. The shielding properties of kombucha’s bacterial cellulose (KBC) were examined using gamma quanta with energies ranging from 122 to 1408 keV and an AmBe neutron source. The native form of KBC contains more than 80% water content. To enhance the radioprotection of kombucha’s biofilm, metallic components (K, Fe, Mxenes) and biological additives were tested. Rhodobacter sphaeroides and Synechocystis sp. PCC6803, which are resistant to oxidative stress, were added to the cultivation media. Physical properties were characterized using microscopy, ion leaching, and contact angle measurements. Post-processed dried KBC wristbands were analyzed for absorption parameters to enhance protective shielding. Possible levels of radioprotection for various types of bacterial cellulose thickness and forms were computed based on the obtained results. The findings encourage the use of bacterial cellulose in a circular economy for future bioregenerative systems.

Complex Issues in the Management of Pericarditis. In Anticipation of the Release of Updated Recommendations of the European Society of Cardiology

With the advent of new diagnostic and therapeutic methods, the management of pericarditis has not become an easier task. The well-studied, but currently rare tuberculosis, bacterial and malignant forms have been joined by pericarditis associated with infection or vaccination against SARS-CoV-2. While 2-3 years ago, cardiologists had to recall the schedule of managing acute viral pericarditis, today its complications are often encountered, including chronic, recurrent, effusive or constrictive pericarditis. The European guidelines were updated 10 years ago and are expected to be issued within the next year. We posed the most pressing questions on the management of pericarditis to the coordinator of the 2015 European Society of Cardiology (ESC) guidelines [1], who will also chair the 2025 ESC guidelines on myocarditis and pericarditis, one of the most cited scientists in the field of inflammatory diseases of the pericardium, Massimo Imazio. He is a Professor in the Department of Cardiology and Anatomy at the University of Turin, runs a school on pericarditis, and has initiated fundamental research of this pathology. We presented his answers with comments of the co-author in the form of a short interview.

Effect of Bacillus subtilis – based microbiological preparations on the numerical composition of cultured forms of endophytic bacteria, content of mineral nutrition elements, photosynthetic pigments, as well as on chlorophyll fluorescence indices in leaves of columnar apple trees

The results of agrochemical field experiments conducted in an orchard of columnar apple tree (Malus domestica Borkh.) in the Moscow Oblast during the period of 2021–2022 are presented. The research objects were the ‘Valuta’, ‘Triumph’, and ‘President’ varieties. The effect of foliar treatments of plants with Bacillus subtilis (strain V167) and Bacillus subtilis (strain V417) strains, as well as Bacillus subtilis – based microbiological preparations “Extrasol” (strain Ch13) and “Phytosporin-M” (strain 26D) on such indicators as the microbiological and chemical composition of leaves, the content of photosynthetic pigments in leaves, and chlorophyll fluorescence indices was studied. Plant samples were analyzed using standard methodology. When applying strains and microbiological preparations based on Bacillus subtilis, the taxonomic composition of endophytic bacterial forms cultured on dense nutrient media and isolated from leaves was represented by the Bacillus genus. For comparison, when treating plants with Bacillus subtilis strain V417 and “Phytosporin-M”, the Pseudomonas genus was also detected. The number of cultivated forms of endophytic bacteria in the treated plants was consistently growing, having reached the maximum value of 406800 CFU/g in the “Extrasol” variant. Notably, the content of photosynthetic pigments in leaves depended on both the plant variety and the strain used. High values of maximal efficiency of PSII photochemistry (Fv/Fm) were observed both in experimental and control variants. A consistent increase in leaf N content was detected when applying “Extrasol”. In this respect, the ‘President’ variety showed the greatest response, i.e., a 16.1 % increase compared to the control. The ‘President’ and ‘Triumph’ varieties demonstrated an increase in leaf K content under the influence of foliar treatment of plants with the studied strains and microbiological preparations. The greatest effect of 17.2 % above the control was observed in the ‘Triumph’ variety when treated with “Extrasol”. Foliar treatments of ‘President’ and ‘Valuta’ plants with microbiological preparations contributed to increased, compared to the control, Mg contents in their leaves.

Modification of Bacillus sp. IMV B-7883 Elastase Activity by the Hetero-Metallic Carboxylatogermanates/Stannates

In recent years, some researchers have found that although many Gram-negative and Gram-positive bacteria secrete elastase, the bacterial forms of elastase have either a low activity or harmful effects. Therefore, further research is needed in isolating and screening microorganisms that produce a high level of elastase activity. Previously we selected strain Bacillus sp. IMV B-7883, which exhibits fairly high elastase activity. To increase its activity, we chose one of the well-known approaches, in particular, the use of a number of coordination compounds capable to influence elastase activity. In this regard, the purpose of this work was to study the effect of such coordination compounds as hetero-metallic carboxylatogermanates/stannates on the elastase activity of Bacillus sp. IMV B-7883. Methods. The object of the investigation was the strain of Bacillus sp., deposited in the Ukrainian Collection of Microorganisms under the number IMV B-7883, isolated from soil. The culture was grown under conditions of submerged cultivation at 28 °С, with a mixing speed of the nutrient medium of 244 rpm for three to six days (72–144 hours). We used an enzyme purified from the supernatant of the culture liquid by precipitation with 90% ammonium sulfate, with further fractionation on neutral and charged carriers. Elastase activity was determined colorimetrically by the intensity of the color of the solution upon enzymatic hydrolysis of elastin stained with Congo red. As modifiers of enzyme activity, hetero-metallic carboxylatogermanates/stannates were used. Results. Of the 15 studied in this work coordination compounds presented by hetero-metallic carboxylatogermanates/stannates, only 1 [Ba(H2O)6][Ge2(OH)2(C6H8O7)2]·nH2O, n=2 and 3 [Ni (H2O)6][Ge2(OH)2(C6H8O7)2]·nH2O, n=4, depending on the concentration used and incubation time, increase the elastase activity by only 3–5%. All other compounds have an inhibitory effect. Conclusions. Obtained data on the inhibitory effect of hetero-metallic carboxylatogermanates/stannates on the elastase activity of Bacillus sp. IMV B-7883 provide new information which may help in solving the issue of the mechanism of interaction between enzymes and complex chemical molecules.

Insights to ballast water: metagenomics as a pressing priority

Metagenomics represents a pivotal development in genomics, offering unprecedented insights into a diverse spectrum of microorganisms, including bacteria, viruses, and fungi, that were previously challenging or impossible to study outside natural environments. Its applications span a remarkable range, from exploring cosmic entities to the depths of our oceans, incorporating numerous analyses. Yet, its utilization in the context of ballast water analysis remains scarce. This highlights the crux of the present review, which aims to showcase the need for metagenomics in ballast water analysis. As is known, ballast water is essential for maintaining ship stability under no cargo conditions or during adverse weather, with daily global movements estimated to be between 3 to 10 billion tonnes. A single bulk cargo ship can transport up to 60,000 tonnes of ballast water for a 200,000-tonne load. It is estimated that over 7,000 species are transported globally in ships' ballast water daily, posing significant ecological risks when these organisms are discharged into new environments where they can become invasive species, disrupting local ecosystems, economies, and human health. Despite the International Maritime Organization setting D-2 standard guidelines and endorsing several ballast water management practices for its safe discharge, the issue persists. This underscores the necessity of employing metagenomics to enhance the monitoring of microbial content in ballast water. The review summarizes some research conducted worldwide to analyze ballast water by metagenomics, all exhibiting diverse microbes, including potent pathogenic bacterial and viral forms. The findings support our view, making metagenomics an invaluable tool to monitor ballast water treatment effectiveness in compliance with evolving environmental regulations. Though the challenges facing metagenomic applications—namely cost, complexity, and the need for comprehensive reference databases—are significant, they will surely be surmountable considering continual technological and methodological advancements. Embracing metagenomics offers a pathway to not only address the ecological threats posed by ballast water transfers but also to safeguard the future of global shipping industries.

Constructing soybean protein isolate /bacterial cellulose co-assemblies by pH shifting treatment: Molecular conformation and physicochemical properties

The study elucidates that the pH shifting treatment unfolds the conformation of soybean protein isolate (SPI), enabling it to intertwine with bacterial cellulose (BC) and form SPI/BC co-assemblies. Results from intrinsic fluorescence spectroscopy and surface hydrophobicity indicate that the SPI with pH shifting treatment shows a notable blue shift in maximum emission wavelength and increased surface hydrophobicity. It demonstrates that pH shifting treatment facilitates the unfolding of SPI's molecular conformation, promoting its entanglement with high aspect ratio BC. Particle size distribution and microstructural analysis further demonstrate that the pH shifting treatment facilitates the formation of SPI/BC co-assemblies. Evaluation of processing properties reveals that the SPI/BC co-assemblies exhibited exceptional gel and emulsification properties, with gel strength and emulsifying activity respectively six and two times higher than natural SPI. This enhancement is attributed to the thickening properties of BC with a high aspect ratio and the superior hydrophobicity of SPI in its molten globule state.

Epidemiology and aetiology of the 2023 meningitis outbreak among children in Iraq.

Meningitis is still a major public health challenge globally. Both the viral and bacterial forms of the disease have been reported worldwide. In 2023, around 200 children with suspected meningitis were admitted to hospital in Halabja Governorate, Iraq. No outbreak of meningitis had been reported previously in that region. To investigate the aetiology and epidemiology of meningitis among children in Halabja Governorate, Iraq, and expedite clinical management and prevention. Blood and cerebrospinal fluid specimens were collected from 197 children admitted to Halabja Paediatric and Maternity Teaching Hospital from 1 March to 1 July 2023 and analysed. The sample t-test was used to compare the haematological, serological and biochemical characteristics of the samples. The majority (76.6%) of the children were aged 2-9 years and 54% were males. The clinical manifestations of the disease were fever (100.0%), headache (89.0%), vomiting (85.7%), and photophobia (72.4%); none of the children had convulsions. The mean values for both neutrophil count and C-reactive protein were statistically significantly raised (P < 0.05) and the red blood cells, white blood cells and neutrophil counts, and lactate dehydrogenase values were statistically significantly raised (P < 0.05). The causative organism was enterovirus (98.5%), with sporadic cases of streptococcal meningitis (1.5%). All the patients recovered fully. The rapid diagnosis of the disease was crucial to the therapeutic and prevention control measures for the outbreak. Although it is still unclear how and where this outbreak started, contaminated drinking water and transmission among children in nurseries and schools are suspected. Further investigations are recommended to determine the source of the enterovirus and identify the virus species and serotypes.

A systematic exploration of bacterial form I rubisco maximal carboxylation rates

Autotrophy is the basis for complex life on Earth. Central to this process is rubisco—the enzyme that catalyzes almost all carbon fixation on the planet. Yet, with only a small fraction of rubisco diversity kinetically characterized so far, the underlying biological factors driving the evolution of fast rubiscos in nature remain unclear. We conducted a high-throughput kinetic characterization of over 100 bacterial form I rubiscos, the most ubiquitous group of rubisco sequences in nature, to uncover the determinants of rubisco’s carboxylation velocity. We show that the presence of a carboxysome CO2 concentrating mechanism correlates with faster rubiscos with a median fivefold higher rate. In contrast to prior studies, we find that rubiscos originating from α-cyanobacteria exhibit the highest carboxylation rates among form I enzymes (≈10 s−1 median versus <7 s−1 in other groups). Our study systematically reveals biological and environmental properties associated with kinetic variation across rubiscos from nature.

Spatial proximity and gene function: a new dimension in prokaryotic gene association network analysis with 3D-GeneNet.

Understanding the biological functions and processes of genes, particularly those not yet characterized, is crucial for advancing molecular biology and identifying therapeutic targets. The hypothesis guiding this study is that the 3D proximity of genes correlates with their functional interactions and relevance in prokaryotes. We introduced 3D-GeneNet, an innovative software tool that utilizes high-throughput sequencing data from chromosome conformation capture techniques and integrates topological metrics to construct gene association networks. Through a series of comparative analyses focused on spatial versus linear distances, we explored various dimensions such as topological structure, functional enrichment levels, distribution patterns of linear distances among gene pairs, and the area under the receiver operating characteristic curve by utilizing model organism Escherichia coli K-12. Furthermore, 3D-GeneNet was shown to maintain good accuracy compared to multiple algorithms (neighbourhood, co-occurrence, coexpression, and fusion) across multiple bacteria, including E. coli, Brucella abortus, and Vibrio cholerae. In addition, the accuracy of 3D-GeneNet's prediction of long-distance gene interactions was identified by bacterial two-hybrid assays on E. coli K-12 MG1655, where 3D-GeneNet not only increased the accuracy of linear genomic distance tripled but also achieved 60% accuracy by running alone. Finally, it can be concluded that the applicability of 3D-GeneNet will extend to various bacterial forms, including Gram-negative, Gram-positive, single-, and multi-chromosomal bacteria through Hi-C sequencing and analysis. Such findings highlight the broad applicability and significant promise of this method in the realm of gene association network. 3D-GeneNet is freely accessible at https://github.com/gaoyuanccc/3D-GeneNet.

Viral Meningitis (Enterovirus) Outbreak in The Pediatric Population of Sulaymaniyah Governorate, Iraq: A Multi-Center Experience

Introduction Viral meningitis, often caused by enteroviruses in children, is prevalent globally but is difficult to distinguish from bacterial forms. Molecular testing like PCR is vital; however. This study investigates the characteristics of viral meningitis in pediatric patients during an outbreak in Sulaymaniyah Governorate, Iraq. Methods This is a multicentered prospective study that included children with a confirmed diagnosis of viral meningitis who have visited pediatric clinics throughout Sulaimani, Halabja, Kalar, and Ranya cities during the period from May 2023 to June 2023. Results In total, 116 cases were included, of whom 75 (64.7%) were male and had a mean age of 6.5 ± 3.2. Most were between the ages of 4-6 (38, 32.8%) and 7-12 years (55, 47.4%). Only 53.4% had contact with another patient. Common symptoms included fever (63.8%) and headache (62.1%). Lymphocyte predominance was observed in 46.6% of CSF samples. Upon molecular diagnosis, the inflammation in all of the cases was due to enterovirus infection. Most of the patients (75%) received empirical antibiotics. The average hospital stay was 10 days. While 95.7% of patients had no complications during recovery, a few experienced issues like weakness and malaise. All had good clinical outcomes. Conclusion The viral meningitis outbreak in Sulaymaniyah Governorate is caused by enterovirus, with epidemiological, clinical, and laboratory findings similar to that of the literature. The condition has resulted in a high prescription rate of empirical antibiotics due to late diagnosis.

Refining antimicrobial photodynamic therapy: effect of charge distribution and central metal ion in fluorinated porphyrins on effective control of planktonic and biofilm bacterial forms

Antibiotic resistance represents a pressing global health challenge, now acknowledged as a critical concern within the framework of One Health. Photodynamic inactivation of microorganisms (PDI) offers an attractive, non-invasive approach known for its flexibility, independence from microbial resistance patterns, broad-spectrum efficacy, and minimal risk of inducing resistance. Various photosensitizers, including porphyrin derivatives have been explored for pathogen eradication. In this context, we present the synthesis, spectroscopic and photophysical characteristics as well as antimicrobial properties of a palladium(II)-porphyrin derivative (PdF2POH), along with its zinc(II)- and free-base counterparts (ZnF2POH and F2POH, respectively). Our findings reveal that the palladium(II)-porphyrin complex can be classified as an excellent generator of reactive oxygen species (ROS), encompassing both singlet oxygen (Φ△ = 0.93) and oxygen-centered radicals. The ability of photosensitizers to generate ROS was assessed using a variety of direct (luminescence measurements) and indirect techniques, including specific fluorescent probes both in solution and in microorganisms during the PDI procedure. We investigated the PDI efficacy of F2POH, ZnF2POH, and PdF2POH against both Gram-negative and Gram-positive bacteria. All tested compounds proved high activity against Gram-positive species, with PdF2POH exhibiting superior efficacy, leading to up to a 6-log reduction in S. aureus viability. Notably, PdF2POH-mediated PDI displayed remarkable effectiveness against S. aureus biofilm, a challenging target due to its complex structure and increased resistance to conventional treatments. Furthermore, our results show that PDI with PdF2POH is more selective for bacterial than for mammalian cells, particularly at lower light doses (up to 5 J/cm2 of blue light illumination). This enhanced efficacy of PdF2POH-mediated PDI as compared to ZnF2POH and F2POH can be attributed to more pronounced ROS generation by palladium derivative via both types of photochemical mechanisms (high yields of singlet oxygen generation as well as oxygen-centered radicals). Additionally, PDI proved effective in eliminating bacteria within S. aureus-infected human keratinocytes, inhibiting infection progression while preserving the viability and integrity of infected HaCaT cells. These findings underscore the potential of metalloporphyrins, particularly the Pd(II)-porphyrin complex, as promising photosensitizers for PDI in various bacterial infections, warranting further investigation in advanced infection models.Graphical abstract

Advances in Therapeutic Strategies for the Management of Clostridioides difficile Infection.

The infection caused by Clostridioides difficile represents one of the bacterial infections with the greatest increase in incidence among nosocomial infections in recent years. C. difficile is a Gram-positive bacterium able to produce toxins and spores. In some cases, infection results in severe diarrhoea and fulminant colitis, which cause prolonged hospitalisation and can be fatal, with repercussions also in terms of health economics. C. difficile is the most common cause of antibiotic-associated diarrhoea in the healthcare setting. The problem of bacterial forms that are increasingly resistant to common antibiotic treatments is also reflected in C. difficile infection (CDI). One of the causes of CDI is intestinal dysmicrobialism induced by prolonged antibiotic therapy. Moreover, in recent years, the emergence of increasingly virulent strains resistant to antibiotic treatment has made the picture even more complex. Evidence on preventive treatments to avoid recurrence is unclear. Current guidelines indicate the following antibiotics for the treatment of CDI: metronidazole, vancomycin, and fidaxomycin. This short narrative review provides an overview of CDI, antibiotic resistance, and emerging treatments.

EFFICACY OF INTRACAMERAL MOXIFLOXACIN VERSUS TOPICAL MOXIFLOXACIN IN PREVENTING ACUTE ENDOPHTHALMITIS AFTER CATARACT SURGERY BY PHACOEMULSIFICATION.

Endophthalmitis is an acute infection of anterior and posterior segment of the eye involving aqueous humour and vitreous cavity along with the other structures. It is classified into many types including bacterial, Fungal, protozoal, viral and atypical forms. Most common route of infection is exogenous either after the surgery or traumatic perforation Objectives were of evaluate the efficacy of intracameral moxifloxacin versus topical moxifloxacin in preventing postoperative acute endophthalmitis after cataract surgery by phacoemulsification. Patients undergoing cataract surgery by phacoemulsification are divided into two groups. Group A and group B. Cataract surgery was performed by phacoemulsification in both the groups by the same consultant. Group A was given 0.5% intracameral moxifloxacin 0.1ml undiluted at the end of surgery and Group B received topical moxifloxacin eyedrops and no intracameral medicine at the end of surgery. Post-operative medicine in both the groups was same for 1st twenty-four hours that is topical dexamethasone 0.1%. Postoperative assessment was made on the next day or after twenty-four hours of surgery Our primary outcome was incidence of postoperative acute endophthalmitis. The study comprised 150 eyes of patients. There were 75 patients in Group A (intracameral moxifloxacin) and 75 patients in Group B (Topical group). Mean age of the patients was 58 years. No case of endophthalmitis was reported in group A (intracameral moxifloxacin). Three cases in group A had acute toxic anterior segment with moderate corneal oedema and severe anterior chamber reaction which resolved in a week time without intravitreal medication. Group B (Topical Moxifloxacin) did not report any case of endophthalmitis. The difference between the two groups was very mild anterior chamber reaction in intracameral group as compared to topical group. 0.1 ml undiluted intracameral moxifloxacin 0.5% can be given as a last step in cataract surgery by phacoemulsification to prevent postoperative acute endophthalmitis infection. This drug administration is not totally safe as our three cases developed drug reaction with moderate corneal oedema and anterior chamber reaction that resolved in a week time.

Methods of active drainage of the maxillary sinus

This study is devoted to the analysis of the practical experience of specialists in the field of otorhinolaryngology on the issue of puncture drainage of the maxillary sinus for bacterial sinusitis. The article provides an overview of historically significant and modern methods of active drainage of the maxillary sinus. It has been established that puncture treatment remains an effective method of treating bacterial forms of maxillary sinusitis.

The microbial status of bee families Apis melifera during the winter period

Introduction. Bees are very important to balancing different ecosystems around the globe. It’s worth noting that, like animals and humans, bees are affected by different pathogens, such as bacteria, viruses, ecto- and endoparasites, and fungi. Therefore, the health of bee families depends on the veterinary sanitary measures undertaken by the beekeepers in close contact with the veterinarians. The aim of the research is to analyze the impact of the microbial status of bee families during the winter period.&#x0D; Material and methods. The research consisted of bee families from the experimental apiary of the Institute of Microbiology and Biotechnology of the Technical University of Moldova. Samples of dead bees, about 50 from each examined hive, were collected for bacteriological research. The morphological properties of the bacterial colonies were studied.&#x0D; Results. The obtained results demonstrate that a diverse microbial microflora prevails in bee families during the winter period. The results of microscopic investigations confirmed the presence of bacteria of the genus E. coli, accounting for over 50% of bacterial forms, followed by Streptococcus and Staphylococcus with a level of 30%, fungal flora 15%, and up to 5% bacteria of the genus Salmonella spp.&#x0D; Conclusions. The bacteriological research carried out in bee families after the winter period reproduces the data of persistent bacteriocenosis in bee families during the cold period of the year and allows for predicting the risk of infectious diseases in bees.

The prevalence of multidrug-resistant Staphylococcus aureus isolated from different clinical samples

Abstract Background: Antibiotic resistance is a major global issue, with Staphylococcus aureus being one of the most common resistant bacterial forms. Objective: The study’s goal was to determine the prevalence of multidrug-resistant (MDR) S. aureus isolated from clinical specimens. Materials and Methods: The standard microbiological techniques used for isolates identification were subsequently validated by the VITEK-2 system. Antibiotic susceptibility was assessed using the disc diffusion technique. MDR bacteria were those that were resistant to three or more antibiotics. Results: S. aureus prevalence in clinical isolates was 27.9%. There was significant resistance toward all antibiotics used in the study except for tetracycline. About 98.2% of the isolates were MDR. Conclusion: Our results underscore the need for continued antibiotic resistance monitoring in S. aureus isolates associated with hospital-acquired infections.

Clinical Chronicle: The Use of Ventriculo-Atrial Shunt in Tuberculous Hydrocephalus Treatment

Tuberculous meningitis (TBM) is the predominant bacterial meningitis form in children under 13, with an incidence of 8.6 per 100,000 before age 15. Tuberculous Hydrocephalus (TH), often presenting with hydrocephalus, poses a significant challenge in Indonesia for both children and adults. The commonly used Ventriculo-peritoneal (VP)-shunt procedure for TH, though prevalent, is associated with multiple complications. As an alternative, the Ventriculo-atrial (VA)-shunt procedure has been explored, but reports on its use in TH in Indonesia are lacking. This case report details a 1-year-old girl with TH who initially underwent a VP-shunt procedure, which proved unsuccessful. Subsequently, the VA-shunt procedure was employed, leading to a complete recovery. Our findings contribute valuable insights into the potential effectiveness of the VA-shunt as an alternative intervention for TH, especially in the Indonesian medical landscape.

Non-traumatic Keratitis: Epidemio-Clinical, Etiological and Therapeutic Aspects at Bouake Hospital

Aim: To contribute to the knowledge and improvement of the management of non-traumatic keratitis. Materials and methods: Retrospective descriptive study based on the analysis of 105 patient records received at the ophthalmology department of Bouaké University Hospital from January 1, 2018, to June 30, 2019, for non-traumatic corneal lesions with or without associated signs. Results: The prevalence was 2.41%. The mean age of patients was 38.52 years with extremes of 1 and 86 years. Males predominated (59.05%), with a sex ratio of 1.44. The main general risk factors were atopy (79.54%). History of ocular trauma was the predominant ocular risk factor (54.17%). Non-infectious keratitis predominated (54.29%). The main etiology was allergy (54.38%). Infectious keratitis was dominated by bacterial forms (60.41%). Treatment was predominantly topical, with antiallergic (23.81%) and antibiotic (65.71%) agents. Conclusion: Non-traumatic keratitis is a serious and life-threatening condition. They occur most frequently in young adult males. The severity of the lesions observed in this condition calls for early management and patient education.

Enhancing cadmium phytoremediation of Chlorophytum comosum (Thunb.) Jacques by applying cadmium-resistant bacterial tablet.

This study aims to formulate bacterial tablets of cadmium (Cd)-resistant Micrococcus sp. MU1, an indole-3-acetic acid-producer, for soil inoculation to improve Cd phytoremediation by Chlorophytum comosum (Thunb.) Jacques. The viability of Micrococcus sp. MU1 in tablets after storage at room temperature and 4 °C was determined. The ability of Micrococcus sp. tablets and cell suspensions on stimulating growth and Cd accumulation in C. comosum was compared. The results found that the viability of Micrococcus sp. tablets stored at room temperature and 4 °C for 2 months were 29.2 and 97.9%, respectively. After 2 months of growth in pots, the dry biomass weights of C. comosum amended with Micrococcus sp. tablet and cell suspension were greater than that of uninoculated control by 1.4- and 1.3-fold, respectively. Cd concentrations in the roots and shoots of C. comosum inoculated with bacterial tablet and bacterial suspension were not significantly different (p < 0.05) and were greater than that of the uninoculated plants. In addition, plants inoculated with Micrococcus sp. tablet and cell suspension exhibited superior phytoextraction performance, bioaccumulation factor, and translocation factor, indicating equal performance of both bacterial forms on boosting Cd phytoremediation efficiency in C. comosum. These findings suggest that soil inoculation with Micrococcus sp. tablet as a ready-to-use inoculum is a novel approach to promote phytoremediation of C. comosum in Cd-contaminated agricultural soil.

Dihydropyrimidine dehydrogenase from Escherichia coli: Transient state analysis reveals both reductive activation prior to turnover and diminished substrate effector roles relative to the mammalian form

Dihydropyrimidine dehydrogenase (DPD) is an enzyme that uses an elaborate architecture to catalyze a simple net reaction: the reduction of the vinylic bond of uracil and thymine. Known DPDs have two active sites separated by approximately 60 Å. One active site has an FAD cofactor and binds NAD(P) and the other has an FMN cofactor and binds pyrimidines. The intervening distance is spanned by four Fe4S4 centers that act as an electron conduit. Recent advancements with porcine DPD have revealed unexpected chemical sequences where the enzyme undergoes reductive activation by transferring two electrons from NADPH to the FMN via the FAD such that the active form has the cofactor set FAD•4(Fe4S4)•FMNH2. Here we describe the first comprehensive kinetic investigation of a bacterial form of DPD. Using primarily transient state methods, DPD from E. coli (EcDPD) was shown to have a similar mechanism to that observed with the mammalian form in that EcDPD is observed to undergo reductive activation before pyrimidine reduction and displays half-of-sites activity. However, two distinct aspects of the EcDPD reaction relative to the mammalian enzyme were observed that relate to the effector roles for substrates: (i) the enzyme will rapidly take up electrons from NADH, reducing a flavin in the absence of pyrimidine substrate, and (ii) the activated form of the enzyme can become fully oxidized by transferring electrons to pyrimidine substrates in the absence of NADH.