Innovative approaches in nanotechnology provide a potentially promising alternative to untreatable cases of mastitis caused by genus Prototheca spp. algae infections. Drying of the teats of the affected animals or culling are typically the outcomes of mastitis in dairy cattle caused by these pathogens. A major issue in both veterinary medicine and animal breeding is the Prototheca species\' widespread resistance to the current methods of managing infections and the available drugs, including antibiotics. Commercial antifungal preparations are also ineffective. Nanotechnology, an emerging discipline, has the potential to create an effective alternative treatment for protothecal mastitis. The aim of the paper is to combine the literature data on the use of nanotechnology in the control of mastitis, taking into account data on combating mastitis caused by Prototheca spp. infections. The databases employed were PubMed, Google Scholar, and Scopus, focusing on literature from the last 20 years to ensure relevance and currency. Studies conducted in vitro have demonstrated that nanomaterials have significant biocidal activity against mastitis infections of different etiologies. Analyzed research papers show that (NPs), such as AgNPs, CuNPs, AuNPs, etc., may not negatively impact various cell lines and may be effective agents in reducing the pathogens\' viability. However, it is also critical to assess the risks involved in using nanomaterials.

Prototheca wickerhamii is a rare cause of cutaneous and systemic infection that requires long treatment courses with potentially toxic medications. We describe a patient with cutaneous protothecosis refractory to triazole monotherapy who experienced clinical and radiographic improvement with the novel oral lipid nanocrystal formulation of amphotericin B without experiencing toxicity.

The majority of the nearly 10,000 described species of green algae are photoautotrophs; however, some species have lost their ability to photosynthesize and become obligate heterotrophs that rely on parasitism for survival. Two high-quality genomes of the heterotrophic algae Prototheca zopfii Pz20 and Pz23 were obtained using short- and long-read genomic as well as transcriptomic data. The genome sizes were 31.2 Mb and 31.3 Mb, respectively, and contig N50 values of 1.99 Mb and 1.26 Mb. Although P. zopfii maintained its plastid genome, the transition to heterotrophy led to a reduction in both plastid and nuclear genome size, including the loss of photosynthesis-related genes from both the nuclear and plastid genomes and the elimination of genes encoding for carotenoid oxygenase and pheophorbide an oxygenase. The loss of genes, including basic leucine-zipper (bZIP) transcription factors, flavin adenine dinucleotide-linked oxidase, and helicase, could have played a role in the transmission of autotrophy to heterotrophs and in the processes of abiotic stress resistance and pathogenicity. A total of 66 (1.37%) and 73 (1.49%) genes were identified as potential horizontal gene transfer events in the two P. zopfii genomes, respectively. Genes for malate synthase and isocitrate lyase, which are horizontally transferred from bacteria, may play a pivotal role in carbon and nitrogen metabolism as well as the pathogenicity of Prototheca and non-photosynthetic organisms. The two high-quality P. zopfii genomes provide new insights into their evolution as obligate heterotrophs and pathogenicity.
OBJECTIVE: The genus Prototheca, characterized by its heterotrophic nature and pathogenicity, serves as an exemplary model for investigating pathobiology. The limited understanding of the protothecosis infectious disease is attributed to the lack of genomic resources. Using HiFi long-read sequencing, both nuclear and plastid genomes were generated for two strains of P. zopfii. The findings revealed a concurrent reduction in both plastid and nuclear genome size, accompanied by the loss of genes associated with photosynthesis, carotenoid oxygenase, basic leucine-zipper (bZIP) transcription factors, and others. The analysis of horizontal gene transfer revealed the presence of 1.37% and 1.49% bacterial genes, including malate synthase and isocitrate lyase, which play crucial roles in carbon and nitrogen metabolism, as well as pathogenicity and obligate heterotrophy. The two high-quality P. zopfii genomes represent valuable resources for investigating their adaptation and evolution as obligate heterotrophs, as well as for developing future prevention and treatment strategies against protothecosis.

Phytochemicals isolated from essential oils are effective alternatives for inhibiting microbial pathogens. Bovine protothecal mastitis is the cause of a reduction in milk production and the secretion of thin, watery milk with white flakes. In the present study, we performed in vitro susceptibility testing of the phytochemicals carvacrol, citral, and thymol in Prototheca strains isolated from cases of protothecosis in small animals and cow feces. The susceptibility of the algae to carvacrol, citral, and thymol was assessed using the modified CLSI M27-A3 broth microdilution method. The ranges of the minimum inhibitory concentrations (MIC%) of the phytochemicals in all isolates were 0.03% to 0.125% for carvacrol, 0.03% to 0.25% for citral, and 0.06% to 0.25% for thymol. Based on these results, carvacrol, citral, and thymol appear effective against Prototheca species at the tested concentrations, and may thus be useful for environmental disinfection in barns.

BACKGROUND: Human protothecosis is an uncommon infection caused by Prototheca spp that rarely infects humans.
OBJECTIVE: Description of a rare disease and a review of its articles.
METHODS: We reported a 24-year-old man who presented with red-brown papules and plaques on the trunk\'s lateral side. We reviewed the literature about disseminated protothecosis and reported our experience with a patient with protothecosis between 2021 and 2023.
RESULTS: Overall, 54 cases of disseminated protothecosis were evaluated, 39 were due to P. wickerhamii, 12 were due to P. zopfii (22.2%), and three were due to Prototheca spp. We found that males were more affected (37 cases, 68.5%) than females (16 cases, 29.6%). The mean age of patients was 39.53 ± 22.48 years. However, disseminated protothecosis can affect people of any age (1-80 years). In contrast to P. wickerhamii, which causes blood, skin, brain, and gastrointestinal tract infections, P. zopfii was mainly found in the blood (7/22) and did not have a significant difference in the mortality rate (P = 0.11).
CONCLUSIONS: Disseminated protothecosis is a rare disease in immunocompromised patients but is generally rarer in immunocompetent hosts. Several underlying disorders include immunocompromised patients, prolonged application of steroids, diabetes mellitus, malignancies, organ transplantation, AIDS, and surgeries. Amphotericin B has been the most effective agent for protothecosis and is reserved for visceral and disseminated infections. Regarding localized cutaneous types, excision or surgical debridement is used.
CONCLUSIONS: Mulberry\'s appearance and appropriate cultural environments are helpful in diagnosing it.

Yeast infections are challenging human and animal medicine due to low rates of detection and the emergence of unknown ecology isolates. The aim of this study was to verify the biochemical identification of yeasts and yeast-like microorganisms obtained from animals comparing the results with chromogenic media and matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF MS). Between January and August 2023, yeast and yeast-like isolates from samples of animals with suspicion of mycosis were identified using Vitek® 2 Compact, Brilliance® Candida Agar and MALDI Biotyper® MSP. A total of 39 cases were included, and 45 isolations were obtained. Cryptococcus neoformans (15.5%, 7/45), Meyerozyma guilliermondii (13.3%, 6/45), Candida parapsilosis (11.1%, 5/45), Candida albicans and Candida tropicalis (8.9%, each one 4/45) were the most identified organisms. There was full agreement with the three identification methods in 71.1% (32/45) of the isolates, disagreement on species in 17.8% (8/45), disagreement on genus and species in 6.7% (3/45) and, in 4.4% (2/45), there was no matched pattern in MALDI-TOF to compare the results. Biochemical methods are a good option in laboratories where proteomics are not available, and chromogenic media enhances diagnostics by detecting mixed infections. Surveillance must be implemented to improve the detection of agents shared between humans and animals.

BACKGROUND: Protothecosis is an infection of humans and animals caused by a rare conditionally pathogenic fungus (prototheca). It can occur in immunocompromised or normal patients.
OBJECTIVE: To describe the epidemiology of prototheca infection in China.
METHODS: We report a case of successful treatment of cutaneous protothecosis with fluconazole and analyzed the epidemiological characteristics, risk factors, clinical manifestations, diagnosis, treatment and prognosis of prototheca infections in China.
RESULTS: We describe this case and 29 cases of prototheca infections in China. At present, Prototheca wickerhamii (Pw) infection is the most common infection in China, and single or combined itraconazole is the preferred treatment.
CONCLUSIONS: These results provide detailed information and relevant clinical treatment strategies for the diagnosis and treatment of protothecosis in China.

Prototheca bovis is an algal emerging pathogen in dairy farms causing refractory protothecal mastitis with increasing incidence worldwide and significant economic impact. P. bovis infects cows throughout the lactation cycle, including dry periods, and can persist in the udder and the environment for a long time. Since P. bovis does not respond to treatments with antibiotics, the suggested sanitary measure to restrict the spread is culling infected animals. A point-of-care test for early detection of the causative agent is critically needed to guide farm management and the appropriate treatment of mastitis. Loop-mediated isothermal amplification (LAMP) is a highly specific molecular method, time-saving, cost-effective and easy to perform in limited settings. This study aimed to develop a LAMP assay for P. bovis detection directly from milk samples; it was employed in conjunction with a commercial DNA extraction kit which was previously used to extract DNA from milk specimens containing microbes. The LAMP assay detected P. bovis DNA within 1 h in milk samples spiked with P. bovis at a concentration of 50 cells/μL, enabling on-farm disease monitoring and decision-making based on a reliable diagnosis. The LAMP method will contribute to the accurate and rapid identification of P. bovis in asymptomatic or recurrent mastitis cases and consequently aid the implementation of targeted control measures and the reduction of losses in milk production.

Prototheca infections are rare in cats, and they are usually associated with cutaneous or subcutaneous infections by P. wickerhamii, with no evidence of neurological signs or systemic disease. In this study, we report the identification of prototheca in the cerebrospinal fluid (CSF) of a cat with neurological symptoms. Fourteen CSF samples were gathered from cats presented with neurological disease between 2012 and 2014. The inclusion criteria for the samples were an increase in CSF protein and cell number (pleocytosis), suggestive of an infectious inflammatory status of the central nervous system (CNS). Nine samples fulfilled the inclusion criteria (inflammatory samples), while five samples, used as control, did not (non-inflammatory samples). All the samples were screened molecularly for different pathogens associated with CNS disease in cats, including prototheca. Out of 14 CSF samples, only one inflammatory sample tested positive for prototheca. Upon sequence and phylogenetic analysis of the amplicon, the strain was characterized as P. bovis. This report is the first documented evidence of prototheca in the cerebrospinal fluid of a cat with neurological signs. Prototheca should be considered in the diagnostics procedures on the CNS of cats presented with infectious diseases.

Better understanding of the molecular mechanisms behind bovine mastitis is fundamental for improving the management of this disease, which continues to be of major concern for the dairy industry, especially in its subclinical form. Disease severity and progression depend on numerous aspects, such as livestock genetics, and the interaction between the causative agent, the host, and the environment. In this context, epigenetic mechanisms have proven to have a role in controlling the response of the animal to inflammation. Therefore, in this study we aimed to explore genome-wide DNA methylation of milk somatic cells (SC) in healthy cows (n = 15) and cows affected by naturally occurring subclinical mastitis by Streptococcus agalactiae (n = 12) and Prototheca spp. (n = 11), to better understand the role of SC methylome in the host response to disease. Differentially methylated regions (DMR) were evaluated comparing: (1) Strep. agalactiae-infected versus healthy; (2) Prototheca-infected versus healthy, and (3) mastitis versus healthy and (4) Strep. agalactiae-infected versus Prototheca-infected. The functional analysis was performed at 2 levels. To begin with, we extracted differentially methylated genes (DMG) from promoter DMR, which were analyzed using the Cytoscape ClueGO plug-in. Coupled with this DMG-driven approach, all the genes associated with promoter-methylated regions were fed to the Pathifier algorithm. From the DMR analysis, we identified 1,081 hypermethylated and 361 hypomethylated promoter regions in Strep. agalactiae-infected animals, while 1,514 hypermethylated and 358 hypomethylated promoter regions were identified in Prototheca-infected animals, when compared with the healthy controls. When considering infected animals as a whole group (regardless of the pathogen), we found 1,576 hypermethylated and 460 hypomethylated promoter regions. Both pathogens were associated with methylation differences in genes involved in pathways related to meiosis, reproduction and tissue remodeling. Exploring the whole methylome, in subclinically infected cows we observed a strong deregulation of immune-related pathways, such as nuclear factor kB and toll-like receptors signaling pathways, and of energy-related pathways such as the tricarboxylic acid cycle and unsaturated fatty acid biosynthesis. In conclusion, no evident pathogen-specific SC methylome signature was detected in the present study. Overall, we observed a clear regulation of host immune response driven by DNA methylation upon subclinical mastitis. Further studies on a larger cohort of animals are needed to validate our results and to possibly identify a unique SC methylome that signifies pathogen-specific alterations.