What is motion? Recent advances in the study of molecular movement patterns of the peptidoglycan synthesis machines

2021 ◽  
Author(s):  
Melissa Mae Lamanna ◽  
Anthony T. Maurelli

How proteins move through space and time is a fundamental question in biology. While great strides have been made towards a mechanistic understanding of protein movement, many questions remain. We discuss the biological implications of motion in the context of the peptidoglycan (PG) synthesis machines. We review systems in several bacteria, including Escherichia coli , Bacillus subtilis , and Streptococcus pneumoniae , and present a comprehensive view of our current knowledge regarding movement dynamics. Discrepancies are also addressed since “one size does not fit all”. For bacteria to divide, new PG is synthesized and incorporated into the growing cell wall by complex multi-protein nanomachines consisting of PG synthases (transglycosylases [TG] and/or transpeptidases [TP]) as well as a variety of regulators and cytoskeletal factors. Advances in imaging capabilities and labeling methods have revealed that these machines are not static but rather circumferentially transit the cell via directed motion perpendicular to the long axis of model rod-shaped bacteria such as E. coli and B. subtilis . The enzymatic activity of the TG:TPs drives motion in some species, while motion is mediated by FtsZ treadmilling in others. In addition, both directed and diffusive motion of the PG synthases has been observed using single particle tracking technology. Here, we examine the biological role of diffusion regarding transit. Lastly, findings regarding the monofunctional transglycosylases (RodA and FtsW) as well as the Class A PG synthases are discussed. This minireview serves to showcase recent advances, broach mechanistic unknowns, and stimulate future areas of study.

2019 ◽  
Vol 18 (14) ◽  
pp. 1991-2005 ◽  
Author(s):  
Habib Zarredar ◽  
Khalil Ansarin ◽  
Behzad Baradaran ◽  
Najibeh Shekari ◽  
Shirin Eyvazi ◽  
...  

Background: MicroRNAs (miRNAs) play an important role in the regulation of various genes involved in cell growth, development and the maintenance of body homeostasis. They are closely linked to different human diseases, particularly in cancers. Amplification and overexpression of some miRNAs that are called ‘oncomiRs’ or down-regulation of tumor suppressor miRNAs are associated with genetic alterations that are sufficient to drive tumorigenesis in humans. Lung cancer is the leading cause of cancer-related deaths worldwide. The high mortality rate of lung cancer is not changed even with recent advances in cancer treatment. Several studies demonstrated that miRNAs are involved in the pathogenesis of lung cancer that they negatively or positively regulate gene and protein expression by acting as oncogenes or tumor suppressors. Objective: This article reviewed the current knowledge on the role of miRNAs and their target genes in lung cancer and discussed the potential use of some miRNAs as novel therapeutic agents in lung cancer. Method: Firstly, we collected and summarized all research and review and research articles in databases including Scopus and PubMed. Then, we used related keywords that are important to lung cancer target therapy and their diagnostic and prognostic values. Results: Based on collected articles and research, recognizing critical microRNA and controlling the expression of this microRNA by antagonist oligonucleotides like antagomiRs or anti-miRs and microRNA mimicking will have a remarkable role in treating lung cancer. Conclusion: Many research studies have shown that a combination of chemotherapy plus knockdown or mimicking microRNA is effective and useful in the cancers treatment like lung cancer.


2020 ◽  
Vol 9 (3) ◽  
pp. 17
Author(s):  
Eric Banan-Mwine Daliri ◽  
Fred Kwame Ofosu ◽  
Ramachandran Chelliah ◽  
Byong Hoon Lee ◽  
Deog-Hwan Oh

Recent advances in microbiome studies have revealed much information about how the gut virome, mycobiome, and gut bacteria influence health and disease. Over the years, many studies have reported associations between the gut microflora under different pathological conditions. However, information about the role of gut metabolites and the mechanisms by which the gut microbiota affect health and disease does not provide enough evidence. Recent advances in next-generation sequencing and metabolomics coupled with large, randomized clinical trials are helping scientists to understand whether gut dysbiosis precedes pathology or gut dysbiosis is secondary to pathology. In this review, we discuss our current knowledge on the impact of gut bacteria, virome, and mycobiome interactions with the host and how they could be manipulated to promote health.


Cancers ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 2078
Author(s):  
Miho Ogawa ◽  
Kazuaki Yokoyama ◽  
Seiya Imoto ◽  
Arinobu Tojo

With the recent advances in noninvasive approaches for cancer diagnosis and surveillance, the term “liquid biopsy” has become more familiar to clinicians, including hematologists. Liquid biopsy provides a variety of clinically useful genetic data. In this era of personalized medicine, genetic information is critical to early diagnosis, aiding risk stratification, directing therapeutic options, and monitoring disease relapse. The validity of circulating tumor DNA (ctDNA)-mediated liquid biopsies has received increasing attention. This review summarizes the current knowledge of liquid biopsy ctDNA in hematological malignancies, focusing on the feasibility, limitations, and key areas of clinical application. We also highlight recent advances in the minimal residual disease monitoring of leukemia using ctDNA. This article will be useful to those involved in the clinical practice of hematopoietic oncology.


2006 ◽  
Vol 73 ◽  
pp. 109-119 ◽  
Author(s):  
Chris Stockdale ◽  
Michael Bruno ◽  
Helder Ferreira ◽  
Elisa Garcia-Wilson ◽  
Nicola Wiechens ◽  
...  

In the 30 years since the discovery of the nucleosome, our picture of it has come into sharp focus. The recent high-resolution structures have provided a wealth of insight into the function of the nucleosome, but they are inherently static. Our current knowledge of how nucleosomes can be reconfigured dynamically is at a much earlier stage. Here, recent advances in the understanding of chromatin structure and dynamics are highlighted. The ways in which different modes of nucleosome reconfiguration are likely to influence each other are discussed, and some of the factors likely to regulate the dynamic properties of nucleosomes are considered.


2020 ◽  
Vol 48 (2) ◽  
pp. 429-439 ◽  
Author(s):  
Jorge Gago ◽  
Danilo M. Daloso ◽  
Marc Carriquí ◽  
Miquel Nadal ◽  
Melanie Morales ◽  
...  

Besides stomata, the photosynthetic CO2 pathway also involves the transport of CO2 from the sub-stomatal air spaces inside to the carboxylation sites in the chloroplast stroma, where Rubisco is located. This pathway is far to be a simple and direct way, formed by series of consecutive barriers that the CO2 should cross to be finally assimilated in photosynthesis, known as the mesophyll conductance (gm). Therefore, the gm reflects the pathway through different air, water and biophysical barriers within the leaf tissues and cell structures. Currently, it is known that gm can impose the same level of limitation (or even higher depending of the conditions) to photosynthesis than the wider known stomata or biochemistry. In this mini-review, we are focused on each of the gm determinants to summarize the current knowledge on the mechanisms driving gm from anatomical to metabolic and biochemical perspectives. Special attention deserve the latest studies demonstrating the importance of the molecular mechanisms driving anatomical traits as cell wall and the chloroplast surface exposed to the mesophyll airspaces (Sc/S) that significantly constrain gm. However, even considering these recent discoveries, still is poorly understood the mechanisms about signaling pathways linking the environment a/biotic stressors with gm responses. Thus, considering the main role of gm as a major driver of the CO2 availability at the carboxylation sites, future studies into these aspects will help us to understand photosynthesis responses in a global change framework.


2020 ◽  
Vol 25 (3) ◽  
pp. 162-173 ◽  
Author(s):  
Sascha Zuber ◽  
Matthias Kliegel

Abstract. Prospective Memory (PM; i.e., the ability to remember to perform planned tasks) represents a key proxy of healthy aging, as it relates to older adults’ everyday functioning, autonomy, and personal well-being. The current review illustrates how PM performance develops across the lifespan and how multiple cognitive and non-cognitive factors influence this trajectory. Further, a new, integrative framework is presented, detailing how those processes interplay in retrieving and executing delayed intentions. Specifically, while most previous models have focused on memory processes, the present model focuses on the role of executive functioning in PM and its development across the lifespan. Finally, a practical outlook is presented, suggesting how the current knowledge can be applied in geriatrics and geropsychology to promote healthy aging by maintaining prospective abilities in the elderly.


1973 ◽  
Vol 29 (02) ◽  
pp. 353-362
Author(s):  
J Lisiewicz ◽  
A Pituch ◽  
J. A Litwin

SummaryThe local Sanarelli-Shwartzman phenomenon (SSP-L) in the skin of 30 rats was induced by an intr a cutaneous sensitizing injection of leukaemic leucocytes isolated from the peripheral blood of patients with chronic lymphocytic leukaemia (CLL), acute myeloblastic leukaemia (AL) and chronic granulocytic leukaemia (CGL) and challenged by an intravenous injection of 100(μ of E. coli endotoxin. SSP-L was observed in 7 rats after injection of CLL lymphocytes and in 6 and 2 rats after AL myeloblasts and the CGL granulocytes, respectively. The lesions in the skin after AL myeloblasts appeared in a shorter time and were of longer duration compared with those observed after CLL lymphocytes and CGL granulocytes. Histologically, the lesions consisted of areas of destruction in the superficial layers of the skin ; the demarcation line showed the presence of neutrophils, macrophages and erythrocytes. Haemorrhages and fibrin deposits near the demarcation line were larger after injection of CLL lymphocytes and AL myeloblasts than after CGL granulocytes. The possible role of leucocyte procoagulative substances in the differences observed have been discussed.


Author(s):  
Pramod Dhakal ◽  
Ankit a Achary ◽  
Vedamurthy Joshi

Bioenhancers are drug facilitator which do not show the typical drug activity but in combination to enhance the activity of other molecule in several way including increase the bioavailability of drug across the membrane, potentiating the drug molecules by conformational interaction, acting as receptor for drug molecules and making target cell more receptive to drugs and promote and increase the bioactivity or bioavailability or the uptake of drugs in combination therapy. The objective of the present study was to evaluate the antibacterial and activity of combination in Azadirachta indica extract with cow urine distillate and pepper extract against common pathogenic bacteria, a causative agent of watery diarrhea. It has been found that Indian indigenous cow urine and its distillate also possess bioenhancing ability. Bioenhancing role of cow urine distillate (CUD) and pepper extract was investigated on antibacterial activity of ethanol extract of Azadirachta indica. Antibacterial activity of ethanol extract neem alone and in combination with CUD and pepper extract were determined the ATCC strains against Staphylococcus aureus, Klebsiella pneumoniae, Pseudomonas aeruginosa and E-coli by cup plate diffusion method. Ethanol extract of neem has showed more effect on P. aeruginosa, E-coli than S. aureus and K. pneumonia with combination of CUD and pepper extract. CUD and pepper did not show any inhibition of test bacteria in low concentration. The antibacterial effect of combination of extract and CUD was higher than the inhibition caused by extract alone and is suggestive of the bioenhancing role of cow urine distillate and pepper. Moreover, inhibition of test bacteria was observed with less concentration of extract on combining with CUD


Author(s):  
Mohamad Hossein Pourhanifeh ◽  
Kazem Abbaszadeh-Goudarzi ◽  
Mohammad Goodarzi ◽  
Sara G.M. Piccirillo ◽  
Alimohammad Shafiee ◽  
...  

: Melanoma is the most life-threatening and aggressive class of skin malignancies. The incidence of melanoma has steadily increased. Metastatic melanoma is greatly resistant to standard anti-melanomatreatments such as chemotherapy, and 5-year survival rate of cases with melanoma who have metastatic form of disease is less than 10%. The contributing role of apoptosis, angiogenesis and autophagy in the pathophysiology of melanoma has been previously demonstrated. Thus, it is extremely urgent to search for complementary therapeutic approachesthat couldenhance the quality of life of subjects and reduce treatment resistance and adverse effects. Resveratrol, known as a polyphenol component present in grapes and some plants, has anti-cancer properties due to its function as an apoptosis inducer in tumor cells, and anti-angiogenic agent to prevent metastasis. However, more clinical trials should be conducted to prove resveratrol efficacy. : Herein, for first time, we summarize current knowledge of anti-cancerous activities of resveratrol in melanoma.


2019 ◽  
Vol 24 (39) ◽  
pp. 4605-4610 ◽  
Author(s):  
Atena Soleimani ◽  
Farzad Rahmani ◽  
Gordon A. Ferns ◽  
Mikhail Ryzhikov ◽  
Amir Avan ◽  
...  

Colorectal cancer (CRC) is the leading cause of cancer death worldwide and its incidence is increasing. In most patients with CRC, the PI3K/AKT signaling axis is over-activated. Regulatory oncogenic or tumor suppressor microRNAs (miRNAs) for PI3K/AKT signaling regulate cell proliferation, migration, invasion, angiogenesis, as well as resistance to chemo-/radio-therapy in colorectal cancer tumor tissues. Thus, regulatory miRNAs of PI3K/AKT/mTOR signaling represent novel biomarkers for new patient diagnosis and obtaining clinically invaluable information from post-treatment CRC patients for improving therapeutic strategies. This review summarizes the current knowledge of miRNAs’ regulatory roles of PI3K/AKT signaling in CRC pathogenesis.


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