scholarly journals Antibiotic and novel compounds manipulation in vitro collagen matrix cells changes extracellular matrix non-complete cell division of fibroblast cells as new dermology technology

2021 ◽  
Author(s):  
Waseem Ahmed
Keyword(s):  
Extracellular Matrix ◽  
Cell Wall ◽  
Cell Division ◽  
Skin Disorder ◽  
Fibroblast Cells ◽  
Inhibition Assay ◽  
Adhatoda Vasica ◽  
Complete Cell ◽  
Novel Antibiotics

Fibroblasts are several cells that are essential for human skin function and regulation process, the underfeed cells are a further issue of skin disorder the current study was based on isolated novel antibiotics compounds comparison of (Chloramphenicol IV) with the changes of Extracellular matrix (RC), inflammatory cells (SC) and non-complete cell division (ICD) effects on fibroblasts cell changes with the cell wall in structural and morphological changes. The new antibiotic compounds were measured and characters in (FTIR) methods with their functional group's analysis of bioactive compounds from Adhatoda vasica and Calotropis procera plants and their effective inhibition concentrations (I C50) extract's against tyrosinase conditions with their activity in vitro enzymatic process, both extracts have higher enzymatic inhibition assay was assessed. The fibroblast cells were compared with Chloramphenicol IV antibiotics with extracted compounds the cell wall was indiscretion and complete shape and structural changes were measured. The higher values of Diphenolase (22.5 μg/mL) was noted in Adhatoda vasica while an IC50 value of Monophenolase was 19.16 μg/mL, which is helpful in the treatment of fibroblast cell disorders, were higher in collagenase inhibition assay, elastase inhibition assay, hyaluronidase inhibition assay, tyrosinase inhibition assay process. It was concluded that novel antibiotics compounds from species could act an as effective role in fibroblast were used in future medicines as sources of locations and creams to control various skin diseases and skin disorder management's processes.

scholarly journals Cytokinesis and Midzone Microtubule Organization inCaenorhabditis elegans Require the Kinesin-like Protein ZEN-4

1998 ◽  
Vol 9 (8) ◽  
pp. 2037-2049 ◽  
Author(s):  
William B. Raich ◽  
Adrienne N. Moran ◽  
Joel H. Rothman ◽  
Jeff Hardin
Keyword(s):  
Cell Division ◽  
Null Allele ◽  
Time Lapse ◽  
Equatorial Region ◽  
Microtubule Organization ◽  
Dividing Cells ◽  
Spindle Midzone ◽  
Cross Links ◽  
Complete Cell

Members of the MKLP1 subfamily of kinesin motor proteins localize to the equatorial region of the spindle midzone and are capable of bundling antiparallel microtubules in vitro. Despite these intriguing characteristics, it is unclear what role these kinesins play in dividing cells, particularly within the context of a developing embryo. Here, we report the identification of a null allele ofzen-4, an MKLP1 homologue in the nematodeCaenorhabditis elegans, and demonstrate that ZEN-4 is essential for cytokinesis. Embryos deprived of ZEN-4 form multinucleate single-celled embryos as they continue to cycle through mitosis but fail to complete cell division. Initiation of the cytokinetic furrow occurs at the normal time and place, but furrow propagation halts prematurely. Time-lapse recordings and microtubule staining reveal that the cytokinesis defect is preceded by the dissociation of the midzone microtubules. We show that ZEN-4 protein localizes to the spindle midzone during anaphase and persists at the midbody region throughout cytokinesis. We propose that ZEN-4 directly cross-links the midzone microtubules and suggest that these microtubules are required for the completion of cytokinesis.

scholarly journals The key bacterial cell division protein FtsZ as a novel antibacterial drug target

2020 ◽  
Author(s):  
Mujeeb Rahman ◽  
Ping Wang ◽  
Na Wang ◽  
Yaodong Chen
Keyword(s):  
Cell Division ◽  
Bacterial Cell ◽  
Drug Targets ◽  
Multidrug Resistant ◽  
Antibacterial Drug ◽  
Bacterial Cell Division ◽  
Bacterial Strains ◽  
Antimicrobial Drugs ◽  
Novel Antibiotics

The number of multidrug-resistant bacterial strains is currently increasing; thus, the determination of drug targets for the development of novel antimicrobial drugs is urgently needed. FtsZ, the prokaryotic homolog of the eukaryotic tubulin, is a GTP-dependent prokaryotic cytoskeletal protein that is conserved among most bacterial strains. In vitro studies revealed that FtsZ self-assembles into dynamic protofilaments or bundles, and it forms a dynamic Z-ring at the center of the cell, leading to septation and consequent cell division. The potential role of FtsZ in the blockage of cell division makes FtsZ a highly attractive target for developing novel antibiotics. Researchers have been working on synthetic molecules and natural products as inhibitors of FtsZ. Accumulating data suggest that FtsZ may provide the platform for the development of novel antibiotics. In this review, we summarize recent advances on the properties of FtsZ protein and bacterial cell division, as well as on the development of FtsZ inhibitors.

scholarly journals Probing for Binding Regions of the FtsZ Protein Surface through Site-Directed Insertions: Discovery of Fully Functional FtsZ-Fluorescent Proteins

2016 ◽  
Vol 199 (1) ◽  
Author(s):  
Desmond A. Moore ◽  
Zakiya N. Whatley ◽  
Chandra P. Joshi ◽  
Masaki Osawa ◽  
Harold P. Erickson
Keyword(s):  
Cell Division ◽  
Fluorescent Proteins ◽  
Sole Source ◽  
Ring Structure ◽  
Content Type ◽  
Z Ring ◽  
Complete Cell ◽  
The Right

ABSTRACT FtsZ, a bacterial tubulin homologue, is a cytoskeletal protein that assembles into protofilaments that are one subunit thick. These protofilaments assemble further to form a “Z ring” at the center of prokaryotic cells. The Z ring generates a constriction force on the inner membrane and also serves as a scaffold to recruit cell wall remodeling proteins for complete cell division in vivo. One model of the Z ring proposes that protofilaments associate via lateral bonds to form ribbons; however, lateral bonds are still only hypothetical. To explore potential lateral bonding sites, we probed the surface of Escherichia coli FtsZ by inserting either small peptides or whole fluorescent proteins (FPs). Among the four lateral surfaces on FtsZ protofilaments, we obtained inserts on the front and back surfaces that were functional for cell division. We concluded that these faces are not sites of essential interactions. Inserts at two sites, G124 and R174, located on the left and right surfaces, completely blocked function, and these sites were identified as possible sites for essential lateral interactions. However, the insert at R174 did not interfere with association of protofilaments into sheets and bundles in vitro. Another goal was to find a location within FtsZ that supported insertion of FP reporter proteins while allowing the FtsZ-FPs to function as the sole source of FtsZ. We discovered one internal site, G55-Q56, where several different FPs could be inserted without impairing function. These FtsZ-FPs may provide advances for imaging Z-ring structure by superresolution techniques. IMPORTANCE One model for the Z-ring structure proposes that protofilaments are assembled into ribbons by lateral bonds between FtsZ subunits. Our study excluded the involvement of the front and back faces of the protofilament in essential interactions in vivo but pointed to two potential lateral bond sites, on the right and left sides. We also identified an FtsZ loop where various fluorescent proteins could be inserted without blocking function; these FtsZ-FPs functioned as the sole source of FtsZ. This advance provides improved tools for all fluorescence imaging of the Z ring and may be especially important for superresolution imaging.

scholarly journals FtsW exhibits distinct processive motions driven by either septal cell wall synthesis or FtsZ treadmilling in E. coli

2019 ◽  
Author(s):  
Xinxing Yang ◽  
Ryan McQuillen ◽  
Zhixin Lyu ◽  
Polly Phillips-Mason ◽  
Ana De La Cruz ◽  
...  
Keyword(s):  
Cell Wall ◽  
Cell Division ◽  
Single Molecule ◽  
Bacterial Cell ◽  
Spatial Information ◽  
Bacterial Species ◽  
E Coli ◽  
Slow Moving

AbstractDuring bacterial cell division, synthesis of new septal peptidoglycan (sPG) is crucial for successful cytokinesis and cell pole morphogenesis. FtsW, a SEDS (Shape, Elongation, Division and Sporulation) family protein and an indispensable component of the cell division machinery in all walled bacterial species, was recently identified in vitro as a new monofunctional peptidoglycan glycosyltransferase (PGTase). FtsW and its cognate monofunctional transpeptidase (TPase) class B penicillin binding protein (PBP3 or FtsI in E. coli) may constitute the essential, bifunctional sPG synthase specific for new sPG synthesis. Despite its importance, the septal PGTase activity of FtsW has not been documented in vivo. How its activity is spatiotemporally regulated in vivo has also remained unknown. Here we investigated the septal PGTase activity and dynamics of FtsW in E. coli cells using a combination of single-molecule imaging and genetic manipulations. We show that FtsW exhibits robust activity to incorporate an N-acetylmuramic acid analog at septa in the absence of other known PGTases, confirming FtsW as the essential septum-specific PGTase in vivo. Notably, we identified two populations of processive moving FtsW molecules at septa. A fast-moving population is driven by the treadmilling dynamics of FtsZ and independent of sPG synthesis. A slow-moving population is driven by active sPG synthesis and independent of FtsZ’s treadmilling dynamics. We further identified that FtsN, a potential sPG synthesis activator, plays an important role in promoting the slow-moving, sPG synthesis-dependent population. Our results support a two-track model, in which inactive sPG synthase molecules follow the fast treadmilling “Z-track” to be distributed along the septum; FtsN promotes their release from the “Z-track” to become active in sPG synthesis on the slow “sPG-track”. This model explains how the spatial information is integrated into the regulation of sPG synthesis activity and suggests a new mechanistic framework for the spatiotemporal coordination of bacterial cell wall constriction.

scholarly journals Peptidoglycan Hydrolases RipA and Ami1 Are Critical for Replication and Persistence of Mycobacterium tuberculosis in the Host

mBio ◽  
2020 ◽  
Vol 11 (2) ◽  
Author(s):  
Claire Healy ◽  
Alexandre Gouzy ◽  
Sabine Ehrt
Keyword(s):  
Cell Wall ◽  
Mycobacterium Tuberculosis ◽  
Cell Division ◽  
Drug Target ◽  
New Drugs ◽  
Chemotherapeutic Regimen ◽  
Content Type ◽  
Cell Wall Polymer ◽  
Redundant Functions

ABSTRACT Synthesis and cleavage of the cell wall polymer peptidoglycan (PG) are carefully orchestrated processes and are essential for the growth and survival of bacteria. Yet, the function and importance of many enzymes that act on PG in Mycobacterium tuberculosis remain to be elucidated. We demonstrate that the activity of the N-acetylmuramyl-l-alanine amidase Ami1 is dispensable for cell division in M. tuberculosis in vitro yet contributes to the bacterium’s ability to persist during chronic infection in mice. Furthermore, the d,l-endopeptidase RipA, a predicted essential enzyme, is dispensable for the viability of M. tuberculosis but required for efficient cell division in vitro and in vivo. Depletion of RipA sensitizes M. tuberculosis to rifampin and to cell envelope-targeting antibiotics. Ami1 helps sustain residual cell division in cells lacking RipA, but the partial redundancy provided by Ami1 is not sufficient during infection, as depletion of RipA prevents M. tuberculosis from replicating in macrophages and leads to dramatic killing of the bacteria in mice. Notably, RipA is essential for persistence of M. tuberculosis in mice, suggesting that cell division is required during chronic mouse infection. Despite the multiplicity of enzymes acting on PG with redundant functions, we have identified two PG hydrolases that are important for M. tuberculosis to replicate and persist in the host. IMPORTANCE Tuberculosis (TB) is a major global heath burden, with 1.6 million people succumbing to the disease every year. The search for new drugs to improve the current chemotherapeutic regimen is crucial to reducing this global health burden. The cell wall polymer peptidoglycan (PG) has emerged as a very successful drug target in bacterial pathogens, as many currently used antibiotics target the synthesis of this macromolecule. However, the multitude of genes encoding PG-synthesizing and PG-modifying enzymes with apparent redundant functions has hindered the identification of novel drug targets in PG synthesis in Mycobacterium tuberculosis. Here, we demonstrate that two PG-cleaving enzymes are important for virulence of M. tuberculosis. In particular, the d,l-endopeptidase RipA represents a potentially attractive drug target, as its depletion results in the clearance of M. tuberculosis from the host and renders the bacteria hypersusceptible to rifampin, a frontline TB drug, and to several cell wall-targeting antibiotics.

Ultrastructure and cell division of an oral bacterium resembling Alysiella filiformis

1973 ◽  
Vol 19 (3) ◽  
pp. 325-327 ◽  
Author(s):  
Gary E. Kaiser ◽  
Marvin J. Starzyk
Keyword(s):  
Cell Wall ◽  
Cell Division ◽  
Epithelial Cells ◽  
Oral Cavity ◽  
Structural Study ◽  
Cell Separation ◽  
Septum Formation ◽  
Innermost Layer ◽  
Oral Bacterium

Alysiella filiformis is commonly found on the epithelial cells of the oral cavity in rabbits. An ultra-structural study of these cells has shown A. filiformis attached by numerous slime appendages (setae) to the host epithelial cells. The organism possesses a multilayered cell wall 18–22 nm thick. Cell division occurs by constriction of the cytoplasm with concurrent septum formation initiating from the dense innermost layer of the cell wall. This is followed by thickening and delamination of the septum with subsequent invagination of the outer layers of the cell wall causing a partial cell separation. However, the cells of the typical trichomes are still held together by septal bridges. Mesosome-like structures were occasionally found and were often in the area of septum formation. All attempts to culture this organism in vitro were unsuccessful.

scholarly journals Structural basis of peptidoglycan endopeptidase regulation

2019 ◽  
Author(s):  
Jung-Ho Shin ◽  
Alan G. Sulpizio ◽  
Aaron Kelley ◽  
Laura Alvarez ◽  
Shannon G. Murphy ◽  
...  
Keyword(s):  
Cell Wall ◽  
Vibrio Cholerae ◽  
Active Site ◽  
Normal Growth ◽  
Structural Basis ◽  
Bacterial Cells ◽  
Cell Wall Digestion ◽  
Novel Antibiotics

AbstractMost bacteria surround themselves with a cell wall, a strong meshwork consisting primarily of the polymerized aminosugar peptidoglycan (PG). PG is essential for structural maintenance of bacterial cells, and thus for viability. PG is also constantly synthesized and turned over, the latter process is mediated by PG cleavage enzymes, for example the endopeptidases (EPs). EPs themselves are essential for growth, but also promote lethal cell wall degradation after exposure to antibiotics that inhibit PG synthases (e.g., β-lactams). Thus, EPs are attractive targets for novel antibiotics and their adjuvants. However, we have a poor understanding of how these enzymes are regulated in vivo, depriving us of novel pathways for the development of such antibiotics. Here, we have solved crystal structures of the LysM/M23 family peptidase ShyA, the primary EP of the cholera pathogen Vibrio cholerae. Our data suggest that ShyA assumes two drastically different conformations; a more open form that allows for substrate binding, and a closed form, which we predicted to be catalytically inactive. Mutations expected to promote the open conformation caused enhanced activity in vitro and in vivo, and these results were recapitulated in EPs from the divergent pathogens Neisseria gonorrheae and Escherichia coli. Our results suggest that LysM/M23 EPs are regulated via release of the inhibitory Domain1 from the M23 active site, likely through conformational re-arrangement in vivo.SignificanceBacteria digest their cell wall following exposure to antibiotics like penicillin. The endopeptidases (EPs) are among the proteins that catalyze cell wall digestion processes after antibiotic exposure, but we do not understand how these enzymes are regulated during normal growth. Herein, we present the structure of the major EP from the diarrheal pathogen Vibrio cholerae. Surprisingly, we find that EPs from this and other pathogens appear to be produced as a largely inactive precursor that undergoes a conformational shift exposing the active site to engage in cell wall digestion. These results enhance our understanding of how EPs are regulated and could open the door for the development of novel antibiotics that overactivate cell wall digestion processes.

scholarly journals In Vitro Development of Porcine Nuclear-Transferred Embryos Derived from Fibroblast Cells Analysed Cytometrically for Apoptosis Incidence and Accuracy of Cell Cycle Synchronization at the G0/G1 Stages / Rozwój In Vitro Klonalnych Zarodków Świni Zrekonstruowanych Z Jąder Komórkowych Fibroblastów Cytometrycznie Analizowanych Pod Kątem Częstotliwości Występowania Śmierci Apoptotycznej I Efektywności Synchronizacji Cyklu Mitotycznego W Fazach G0/G1

2013 ◽  
Vol 13 (4) ◽  
pp. 735-752 ◽  
Author(s):  
Marcin Samiec ◽  
Maria Skrzyszowska ◽  
Michał Bochenek
Keyword(s):  
Cell Cycle ◽  
Cell Division ◽  
Mitotic Cycle ◽  
Apoptotic Cell ◽  
Fibroblast Cell ◽  
Contact Inhibition ◽  
Fibroblast Cells ◽  
Cell Nuclei ◽  
Flow Cytometric

Abstract The study was undertaken to examine whether various strategies, including contact inhibition and serum starvation, that were used for artificial synchronization of mitotic cycle of porcine fibroblast cell lines affect differently the distribution of cell cycle stage frequencies and the occurrence of apoptotic cell death in the analysed cell samples. In vitro cultured (contact-inhibited or serumstarved) somatic cells were subjected to flow cytometric diagnostics of mitotic cycle together with the detection of late-apoptotic cell fractions with hypodiploid number of nuclear DNA molecules. Moreover, impact of the methods applied to synchronize the cell division cycle of different types of nuclear donor fibroblast cells (adult cutaneous and foetal fibroblasts) on the preimplantation developmental outcomes of cloned pig embryos was investigated. The developmental capabilities of nuclear-transferred (NT) embryos that were reconstituted with contact-inhibited or serum-depleted adult cutaneous fibroblast cells to reach the morula and blastocyst stages remained at the levels of 169/278 (60.8%) and 76/278 (27.3%) or 121/265 (45.7%) and 46/265 (17.4%), respectively. The proportions of NT embryos originating from contact-inhibited or serum-deprived foetal fibroblast cells that completed their development to the morula and blastocyst stages were 223/296 (75.3%) and 108/296 (36.5%) or 165/261 (63.2%) and 67/261 (25.7%), respectively. In conclusion, the flow cytometric analysis of cultured porcine adult cutaneous and foetal fibroblast cells revealed the high efficiency of the artificial synchronization of mitotic cycle at the G0/G1 stages as a consequence of applying the methods of either contact inhibition or serum deprivation. For both types of fibroblast cells used to reconstruct the enucleated oocytes, the strategies that were utilized to synchronize the cell division cycle of nuclear donor cells considerably influenced the in vitro developmental abilities of NT pig embryos. Developmental competencies to reach the morula/blastocyst stages for cloned embryos that had been reconstructed with contact-inhibited or serum-starved foetal fibroblast cell nuclei were significantly higher than those for embryos that had been reconstructed with contact-inhibited or serum-starved adult cutaneous fibroblast cell nuclei.

scholarly journals Mitotic chromosome alignment ensures mitotic fidelity by promoting interchromosomal compaction during anaphase

2019 ◽  
Vol 218 (4) ◽  
pp. 1148-1163 ◽  
Author(s):  
Cindy L. Fonseca ◽  
Heidi L.H. Malaby ◽  
Leslie A. Sepaniac ◽  
Whitney Martin ◽  
Candice Byers ◽  
...  
Keyword(s):  
Cell Division ◽  
Postnatal Growth ◽  
Mitotic Chromosomes ◽  
Growth And Survival ◽  
Copy Numbers ◽  
Chromosome Alignment ◽  
Single Nucleus ◽  
Complete Cell

Chromosome alignment at the equator of the mitotic spindle is a highly conserved step during cell division; however, its importance to genomic stability and cellular fitness is not understood. Normal mammalian somatic cells lacking KIF18A function complete cell division without aligning chromosomes. These alignment-deficient cells display normal chromosome copy numbers in vitro and in vivo, suggesting that chromosome alignment is largely dispensable for maintenance of euploidy. However, we find that loss of chromosome alignment leads to interchromosomal compaction defects during anaphase, abnormal organization of chromosomes into a single nucleus at mitotic exit, and the formation of micronuclei in vitro and in vivo. These defects slow cell proliferation and are associated with impaired postnatal growth and survival in mice. Our studies support a model in which the alignment of mitotic chromosomes promotes proper organization of chromosomes into a single nucleus and continued proliferation by ensuring that chromosomes segregate as a compact mass during anaphase.

scholarly journals Role of the Murein Precursor UDP-N-Acetylmuramyl-l-Ala-γ-d-Glu- meso-Diaminopimelic Acid-d-Ala-d-Ala in Repression of β-Lactamase Induction in Cell Division Mutants

2002 ◽  
Vol 184 (15) ◽  
pp. 4233-4239 ◽  
Author(s):  
Tsuyoshi Uehara ◽  
James T. Park
Keyword(s):  
Cell Wall ◽  
Cell Division ◽  
High Ratio ◽  
Diaminopimelic Acid ◽  
Breakdown Product ◽  
A Cell ◽  
Cell Wall Breakdown ◽  
Ts Mutant

ABSTRACT Certain β-lactam antibiotics induce the chromosomal ampC β-lactamase of many gram-negative bacteria. The natural inducer, though not yet unequivocally identified, is a cell wall breakdown product which enters the cell via the AmpG permease component of the murein recycling pathway. Surprisingly, it has been reported that β-lactamase is not induced by cefoxitin in the absence of FtsZ, which is required for cell division, or in the absence of penicillin-binding protein 2 (PBP2), which is required for cell elongation. Since these results remain unexplained, we examined an ftsZ mutant and other cell division mutants (ftsA, ftsQ, and ftsI) and a PBP2 mutant for induction of β-lactamase. In all mutants, β-lactamase was not induced by cefoxitin, which confirms the initial reports. The murein precursor, UDP-N-acetylmuramyl-l-Ala-γ-d-Glu-meso-diaminopimelic acid-d-Ala-d-Ala (UDP-MurNAc-pentapeptide), has been shown to serve as a corepressor with AmpR to repress β-lactamase expression in vitro. Our results suggest that β-lactamase is not induced because the fts mutants contain a greatly increased amount of corepressor which the inducer cannot displace. In the PBP2(Ts) mutant, in addition to accumulation of corepressor, cell wall turnover and recycling were greatly reduced so that little or no inducer was available. Hence, in both cases, a high ratio of repressor to inducer presumably prevents induction.

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