Characterization of highly stable extracellular lipase from the extremely halophilic archaeon Halolamina sp.

Enzymes of the archaea living in extreme environments are resistant to the challenging conditions. Lipase is among the important enzymes used in the industry and agriculture. In this study, the extracellular lipase from extremely halophilic archaeon Halolamina sp. was characterized for the first time. Optimum temperature for the enzyme activity was determined as 70oC, optimum pH was 7.0, and the optimum salt concentration was 3.6 M. Additionally, more than 70% of the enzyme activity was remained between pH 3.0-10.0 for 48 h as well as incubation of the enzyme at 70oC for 30 min increased its activity for 44%, and no activity loss was observed after incubation at 80oC. Also, presence of the metals increased the enzyme activity up to 88%. The enzyme was highly resistant to the organic solvents acetone, methanol, and DMSO while strong inhibition was caused by n-butanol. Among the detergents, the enzyme kept its activity substantially in the presence of SDS; however, other detergents caused inhibition of the enzyme activity. This characterization study showed that the lipase from the haloarchaeon Halolamina sp. is highly stable at the wide ranges of temperature and pH values as well as in the presence of diverse inhibitors. This enzyme is promising to be used in biotechnological applications

Editorial: The utilization of plants in vaccine research

In the framework of active immunization, plants provide a valuable platform that can serve as bio-factory for producing virus-like particles (VLPs) or subunit vaccines and they can also facilitate the direct delivery of these molecules through oral administration. Leveraging plants in vaccine development presents numerous benefits, as they enable the cost-effective production of substantial quantities of target antigens. Additionally, the robust cell walls of these hosts provide protection against proteases in the gastrointestinal tract, rendering plants advantageous for implementing oral vaccination strategies. Plant-derived antigens are safer compared to methods using mammalian cells/tissues which may contain viruses or prions. Additionally, genetic engineering of plants is relatively easy, and they possess the machinery for the post-translational modification of proteins

Immune responses elicited by the recombinant Erp, HspR, LppX, MmaA4, and OmpA proteins from Mycobacterium tuberculosis in mice

Immunogenic potency of the recombinant Erp, HspR, LppX, MmaA4, and OmpA proteins from Mycobacterium tuberculosis (MTB), formulated with Montanide ISA 720 VG adjuvant, was evaluated in BALB/c mice for the first time in this study. The five vaccine formulations, adjuvant, and BCG vaccine were subcutaneously injected into mice, and the sera were collected at days 0, 15, 30, 41, and 66. The humoral and cellular immune responses against vaccine formulations were determined by measuring serum IgG and serum interferon-gamma (IFN-γ) and interleukin-12 (IL-12) levels, respectively. All formulations significantly increased IgG levels post-vaccination. The highest increase in IFN-γ level was provided by MmaA4 formulation. The Erp, HspR, and LppX formulations were as effective as BCG in enhancement of IFN-γ level. The most efficient vaccine boosting the IL-12 level was HspR formulation, especially at day 66. Erp formulation also increased the IL-12 level more than BCG at days 15 and 30. The IL-12 level boosted by MmaA4 formulation was found to be similar to that by BCG. OmpA formulation was inefficient in enhancement of cellular immune responses. This study showed that MmaA4, HspR, and Erp proteins from MTB are successful in eliciting both humoral and cellular immune responses in mice

Boron Stress Responsive MicroRNAs and Their Targets in Barley

Boron stress is an environmental factor affecting plant development and production. Recently, microRNAs (miRNAs) have been found to be involved in several plant processes such as growth regulation and stress responses. In this study, miRNAs associated with boron stress were identified and characterized in barley. miRNA profiles were also comparatively analyzed between root and leave samples. A total of 31 known and 3 new miRNAs were identified in barley; 25 of them were found to respond to boron treatment. Several miRNAs were expressed in a tissue specific manner; for example, miR156d, miR171a, miR397, and miR444a were only detected in leaves. Additionally, a total of 934 barley transcripts were found to be specifically targeted and degraded by miRNAs. In silico analysis of miRNA target genes demonstrated that many miRNA targets are conserved transcription factors such as Squamosa promoter-binding protein, Auxin response factor (ARF), and the MYB transcription factor family. A majority of these targets were responsible for plant growth and response to environmental changes. We also propose that some of the miRNAs in barley such as miRNA408 might play critical roles against boron exposure. In conclusion, barley may use several pathways and cellular processes targeted by miRNAs to cope with boron stress

In silico characterization of the citrate synthase family in Mycobacterium tuberculosis / Mycobacterium tuberculosis’te sitrat sentaz ailesinin in silico karakterizasyonu

AbstractObjective: Mycobacterium tuberculosis (MTB) is an obligate aerobe bacterial pathogen. Here, the citrate synthase (CS) family, an important component of aerobic respiration, was investigated in MTB.Methods: MTB genome was analyzed in silico to reveal the members of CS family. The nucleotide and amino acid sequences were retrieved from the NCBI database, and searched for the similarity using the NCBI BLAST tool. Sequence alignment and phylogenetic analysis were performed using MEGA6. The physicochemical parameters, cellular localization, HMM profiles, motif structure, 3D modeling, and the interactions of the proteins were analyzed using GPMAW, PSORTb, Pfam and SMART, MEME, Phyre2, and STRING databases, respectively.Results: The members of CS family in MTB were identified as CitA, GltA2, and PrpC. The CitA and PrpC were found to be closer in phylogeny than GltA2, and the trees of three proteins were shown to be similar to that constructed based on 16S rRNA in mycobacteria. The CitA contains two CS domains while a single CS domain is found in GltA2 and PrpC. Besides, LHGGA and MGFGHRVY motifs are conserved in MTB and various bacteria. The molecular weight and pI values of CitA, GltA2, and PrpC were calculated as 40.1, 47.9, and 42.9 kDa, and 5.41, 5.35, and 9.31, respectively. Cellular localization of the proteins was predicted as cytoplasm. The highest expression ratio was found to be for gltA2 followed by prpC and citA, respectively, in the retrieved RNA-seq datasets obtained from the aerobic log phase of MTB H37Rv.Conclusion: This comprehensive bioinformatics analysis of CS family in MTB has a contribution to the knowledge of the genetics and physiology of this pathogen.</jats:p

Involvement of retroelements in the autoimmune response in humans

Retroelements are mobile genomic components requiring an RNA intermediate which is reverse-transcribed into complementary DNA for transposition. Human genome contains a vast amount of retroelements including retrotransposons and endogenous retroviruses. These elements are categorized according to presence or absence of long terminal repeats, LTRs or non-LTRs, as well as autonomous and non-autonomous according to involvement of reverse transcriptase. The retroelements have been accumulated in mammalian genomes over all evolutionary times through vertical transmission, and many of them were inactivated through accumulation of mutations. However, the retroelements entered into genome within the last 200,000 years are mostly functional. Some of the active retroelements are associated with varying autoimmune diseases because anti-retroelement antibodies might cross-react with other proteins in the human body. For instance, autoimmunity and inflammation could be stimulated by increased expression of long interspersed element 1 (LINE-1 or L1) or decreased L1 degradation. Different regulation of L1 expression might be related to the genetic and sex-related variations or environmental factors. Activation of retroelements is also controlled by epigenetic silencing mechanisms such as histone modification. Elevated levels of L1 retroelements could trigger the production of type I interferon, a crucial innate defense mechanism in mammals against viruses, and systemic autoimmune response is induced. Loss-of-function in some deoxyribonucleases (DNases) such as three prime repair exonuclease 1 that degrades reverse-transcribed DNA is also related to autoimmune diseases. Additionally, human endogenous retroviruses also play a role in autoimmune diseases. Involvement of retroelements in autoimmune disorders is exemplified with three diseases, i.e. systemic lupus erythematosus, Aicardi–Goutières syndrome, and multiple sclerosis.</jats:p

Applications of Plant Molecular Farming

Vaccines are effective tools for the prophylaxis of infectious diseases. Various diseases have been eradicated using vaccines, and the importance of vaccination has recently been comprehended well in the COVID-19 pandemic. However, access to vaccines is generally limited, especially in least developed countries. Plants have many advantages in subunit vaccine development against infectious diseases, such as safety, lower cost, and delivery of antigens to induce gut-associated mucosal immunity. Antigenic proteins can be produced in plants either stably by integrating the gene of interest into the nuclear or chloroplast genome or transiently using vectors such as viruses. Transgenic plants can produce large amounts of antigen followed by the purification of protein to be used in vaccine formulation. Additionally, antigen-expressing plants can be used in feeding as oral vaccines to induce mucosal immunity in the gut. Various plant-based vaccine candidates have been developed against many viral and bacterial diseases. Some candidates were evaluated in human clinical trials, and the plant-based COVID-19 vaccine Medicago Covifenz®&nbsp;was approved in Canada for human use. Progress in the derivation of vaccines from plants shows promise that plant-based vaccines will be on the agenda more often in the near future.</p