The global scale of the COVID-19 pandemic has demonstrated the evolution of SARS-CoV-2 and the clues of adaptation. After two years and two months since the declaration of the pandemic, several variants have emerged and become fixed in the human population thanks to extrinsic selective pressures but also to the inherent mutational capacity of the virus. Here, we applied a neutral substitution evolution test to the spike (S) protein of Omicron’s protein and compared it to the others’ variant of concern (VOC) neutral evolution. We carried out comparisons among the interactions between the S proteins from the VOCs (Alpha, Beta, Gamma, Delta and Omicron) and the receptor ACE2. The shared amino acids among all the ACE2 binding S proteins remain constant, indicating that these amino acids are essential for the accurate binding to the receptor. The complexes of the RBD for every variant with the receptor were used to identify the amino acids involved in the protein—protein interaction (PPI). The RBD of Omicron establishes 82 contacts, compared to the 74 of the Wuhan original viral protein. Hence, the mean number of contacts per residue is higher, making the contact thermodynamically more stable. The RBDs of the VOCs are similar in sequence and structure; however, Omicron’s RBD presents the largest deviation from the structure by 1.11 Å RMSD, caused by a set of mutations near the glycosylation N343. The chemical properties and structure near the glycosylation N343 of the Omicron S protein are different from the original protein, which provoke reduced recognition by the neutralizing antibodies. Our results hint that selective pressures are induced by mass vaccination throughout the world and by the persistence of recurrent infections in immunosuppressed individuals, who did not eliminate the infection and ended up facilitating the selection of viruses whose characteristics are different from the previous VOCs, less pathogenic but with higher transmissibility.

Coronaviruses interact with protein or carbohydrate receptors through their spike proteins to infect cells. Even if the known protein receptors for these viruses have no evolutionary relationships, they do share ontological commonalities that the virus might leverage to exacerbate the pathophysiology. ANPEP/CD13, DPP IV/CD26, and ACE2 are the three protein receptors that are known to be exploited by several human coronaviruses. These receptors are moonlighting enzymes involved in several physiological processes such as digestion, metabolism, and blood pressure regulation; moreover, the three proteins are expressed in kidney, intestine, endothelium, and other tissues/cell types. Here, we spot the commonalities between the three enzymes, the physiological functions of the enzymes are outlined, and how blocking either enzyme results in systemic deregulations and multi-organ failures via viral infection or therapeutic interventions is addressed. It can be difficult to pinpoint any coronavirus as the target when creating a medication to fight them, due to the multiple processes that receptors are linked to and their extensive expression.

Like the majority of non-communicable diseases that have recently gained attention, functional gastrointestinal (GI) disorders (FGID) in both children and adults are caused by a variety of medical conditions. In general, while it is often thought that common conditions such as obesity may cause other problems, for example, asthma or mental health issues, more consideration needs to be given to the possibility that they could both be brought on by a single underlying problem. Based on the variations in non-communicable disease, in recent years, our group has been revisiting the exact role of the intestinal microbiome within the Vertebrata. While the metabolic products of the microbiome have a role to play in the adult, our tentative conclusion is that the fully functioning, mutualistic microbiome has a primary role: to transfer antigen information from the mother to the neonate in order to calibrate its immune system, allowing it to survive within the microbial environment into which it will emerge. Granted that the microbiome possesses such a function, logic suggests the need for a robust, flexible, mechanism allowing for the partition of nutrition in the mature animal, thus ensuring the continued existence of both the vertebrate host and microbial guest, even under potentially unfavourable conditions. It is feasible that this partition process acts by altering the rate of peristalsis following communication through the gut–brain axis. The final step of this animal–microbiota symbiosis would then be when key microbes are transferred from the female to her progeny, either live offspring or eggs. According to this scheme, each animal inherits twice, once from its parents’ genetic material and once from the mother’s microbiome with the aid of the father’s seminal microbiome, which helps determine the expression of the parental genes. The key point is that the failure of this latter inheritance in humans leads to the distinctive manifestations of functional FGID disorders including inflammation and gut motility disturbances. Furthermore, it seems likely that the critical microbiome–gut association occurs in the first few hours of independent life, in a process that we term handshaking. Note that even if obvious disease in childhood is avoided, the underlying disorders may intrude later in youth or adulthood with immune system disruption coexisting with gut–brain axis issues such as excessive weight gain and poor mental health. In principle, investigating and perhaps supplementing the maternal microbiota provide clinicians with an unprecedented opportunity to intervene in long-term disease processes, even before the child is born.

Chinese hamster ovary (CHO) cells are the preferred system for producing recombinant proteins (RPs), and many have been used effectively in therapies. Specific productivity is related to the intrinsic genetics, biochemical, and metabolic characteristics of each producing clone. Through cell growth, lipids play a crucial role in biology. They serve as energy sources, form the bilayer of organelles and cell membranes, and are involved in the regulation of metabolic stress. To understand lipid requirements during culture, the cellular lipid composition must be considered. However, lipid studies involve complex analytical techniques, such as nuclear magnetic resonance (NMR) and mass spectrometry (MS), which require lengthy processing. Here, we explored the nonpolar and polar lipid composition in CHO cells stained with Nile red (NR), a fluorescent dye with solvatochromic properties, using flow cytometry. We describe a form to determine nonpolar and polar lipids using four different configurations of excitation wavelength laser lines and 10 different wavelength bandpass filters to acquire the fluorescence emission by flow cytometry. We show that the nonpolar and polar lipid composition changes throughout the kinetic growth of three clones of the stably transfected CHO cell line DG44 (CHO‐DG44). Nonpolar lipids tend to increase in the stationary phase while polar lipids progressively decrease throughout the kinetic growth. This study provides insight into changes in lipid composition during the growth phases of CHO cells, which can be used to improve bioprocesses for CHO and other cell lines used for RP production. Practical applications : An increasing number of recombinant proteins are produced in mammalian cells. They are amply used not only in the biomedical field but also in the food industry. A necessary approach to improving the bioprocesses involved in recombinant protein production is to understand and control needed physical parameters such as temperature and oxygen consumption, as well as the required metabolites, by maintaining a continuous record of culture conditions throughout the process. This work describes a procedure for rapidly assessing changes in nonpolar and polar lipids throughout cell culture. This technique could be used to estimate lipid requirements in cell lines used in recombinant protein production and improve culture medium conditions.