scholarly journals Bactericidal/permeability-increasing protein in the reproductive system of male mice may be involved in the sperm–oocyte fusion

Reproduction ◽  
2013 ◽  
Vol 146 (2) ◽  
pp. 135-144 ◽  
Author(s):  
Kun Li ◽  
Yue Liu ◽  
Xiaoyu Xia ◽  
Li Wang ◽  
Meige Lu ◽  
...  
Keyword(s):  
Transport Proteins ◽  
Seminal Vesicles ◽  
Lipid Transport ◽  
Human Neutrophils ◽  
Gram Negative Bacteria ◽  
Male Mice ◽  
Gram Negative ◽  
Major Function ◽  
The Family ◽  
Lps Binding

Bactericidal/permeability-increasing protein (BPI) is a 455-residue (∼55 kDa) protein found mainly in the primary (azurophilic) granules of human neutrophils. BPI is an endogenous antibiotic protein that belongs to the family of mammalian lipopolysaccharide (LPS)-binding and lipid transport proteins. Its major function is to kill Gram-negative bacteria, thereby protecting the host from infection. In addition, BPI can inhibit angiogenesis, suppress LPS-mediated platelet activation, increase DNA synthesis, and activate ERK/Akt signaling. In this study, we found thatBpiwas expressed in the testis and epididymis but not in the seminal vesicles, prostate, and solidification glands. BPI expression in the epididymis increased upon upregulation of testosterone, caused by injection of GNRH. In orchidectomized mice, BPI expression was significantly reduced, but its expression was restored to 30% of control levels in orchidectomized mice that received supplementary testosterone. The number of sperm fused per egg significantly decreased after incubation with anti-BPI antiserum. These results suggest that BPI may take part in the process of sperm–oocyte fusion and play a unique and significant role in reproduction.

scholarly journals Lipopolysaccharide-Trap-Fc, a Multifunctional Agent To Battle Gram-Negative Bacteria

2009 ◽  
Vol 77 (7) ◽  
pp. 2925-2931 ◽  
Author(s):  
Philipp Groß ◽  
Katharina Brandl ◽  
Christine Dierkes ◽  
Jürgen Schölmerich ◽  
Bernd Salzberger ◽  
...  
Keyword(s):  
Myeloid Differentiation ◽  
Gram Negative Bacteria ◽  
Bacterial Sepsis ◽  
Tlr Signaling ◽  
Monocytic Cells ◽  
Gram Negative ◽  
The Family ◽  
Myeloid Differentiation Factor ◽  
Lps Treatment

ABSTRACT The family of Toll-like receptors (TLRs) plays a pivotal role in host defense against pathogens. However, overstimulation of these receptors may lead to uncontrolled general inflammation and eventually to systemic organ dysfunction or failure. With the intent to control overwhelming inflammation during gram-negative bacterial sepsis, we constructed soluble fusion proteins of the lipopolysaccharide (LPS)-receptor complex to modulate TLR signaling in multiple ways. The extracellular domain of mouse TLR4 and mouse myeloid differentiation factor 2 (MD-2) fusions (LPS-Trap) were linked to human immunoglobulin G Fc domains (LPS-Trap-Fc). In addition to the ability to bind LPS or gram-negative bacteria and to inhibit interleukin-6 secretion of monocytic cells after LPS treatment, LPS-Trap-Fc was able to opsonize fluorescent Escherichia coli particles. This led to enhancement of phagocytosis by monocytic cells which was strictly dependent on the presence of the Fc region. Moreover, only LPS-Trap-Fc- and not LPS-Trap-coated bacteria were sensitized to complement killing. Therefore, LPS-Trap-Fc not only neutralizes LPS but also, after binding to bacteria, enhances phagocytosis and complement-mediated killing and could thus act as a multifunctional agent to fight gram-negative bacteria in vivo.

Killing of Gram-Negative Bacteria by Ciprofloxacin within both Healthy Human Neutrophils and Neutrophils with Inactivated O2-Dependent Bactericidal Mechanisms

Chemotherapy ◽  
1999 ◽  
Vol 45 (4) ◽  
pp. 268-276 ◽  
Author(s):  
E. Cantón ◽  
J. Peman ◽  
E. Cabrera ◽  
M. Velert ◽  
A. Orero ◽  
...  
Keyword(s):  
Human Neutrophils ◽  
Gram Negative Bacteria ◽  
Healthy Human ◽  
Gram Negative

scholarly journals LPS-binding protein protects mice from septic shock caused by LPS or gram-negative bacteria.

1998 ◽  
Vol 101 (10) ◽  
pp. 2065-2071 ◽  
Author(s):  
N Lamping ◽  
R Dettmer ◽  
N W Schröder ◽  
D Pfeil ◽  
W Hallatschek ◽  
...  
Keyword(s):  
Septic Shock ◽  
Binding Protein ◽  
Gram Negative Bacteria ◽  
Gram Negative ◽  
Lps Binding

scholarly journals Gram-negative trimeric porins have specific LPS binding sites that are essential for porin biogenesis

2016 ◽  
Vol 113 (34) ◽  
pp. E5034-E5043 ◽  
Author(s):  
Wanatchaporn Arunmanee ◽  
Monisha Pathania ◽  
Alexandra S. Solovyova ◽  
Anton P. Le Brun ◽  
Helen Ridley ◽  
...  
Keyword(s):  
Binding Sites ◽  
Calcium Ion ◽  
Gram Negative Bacteria ◽  
Core Oligosaccharide ◽  
Gram Negative ◽  
X Ray ◽  
Cross Links ◽  
Phosphate Groups ◽  
Positively Charged ◽  
Lps Binding

The outer membrane (OM) of gram-negative bacteria is an unusual asymmetric bilayer with an external monolayer of lipopolysaccharide (LPS) and an inner layer of phospholipids. The LPS layer is rigid and stabilized by divalent cation cross-links between phosphate groups on the core oligosaccharide regions. This means that the OM is robust and highly impermeable to toxins and antibiotics. During their biogenesis, OM proteins (OMPs), which function as transporters and receptors, must integrate into this ordered monolayer while preserving its impermeability. Here we reveal the specific interactions between the trimeric porins of Enterobacteriaceae and LPS. Isolated porins form complexes with variable numbers of LPS molecules, which are stabilized by calcium ions. In earlier studies, two high-affinity sites were predicted to contain groups of positively charged side chains. Mutation of these residues led to the loss of LPS binding and, in one site, also prevented trimerization of the porin, explaining the previously observed effect of LPS mutants on porin folding. The high-resolution X-ray crystal structure of a trimeric porin–LPS complex not only helps to explain the mutagenesis results but also reveals more complex, subtle porin–LPS interactions and a bridging calcium ion.

scholarly journals Multicenter Antimicrobial Susceptibility Survey of Gram-Negative Bacteria Isolated from Patients with Community-Acquired Infections in the People's Republic of China

2006 ◽  
Vol 50 (1) ◽  
pp. 374-378 ◽  
Author(s):  
Thomas K. W. Ling ◽  
Jianhui Xiong ◽  
Yunsong Yu ◽  
Ching Ching Lee ◽  
Huifen Ye ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Antimicrobial Susceptibility ◽  
People’S Republic Of China ◽  
Gram Negative Bacteria ◽  
People's Republic Of China ◽  
Gram Negative ◽  
Republic Of China ◽  
Extended Spectrum ◽  
The Family

ABSTRACT A survey of 2,099 gram-negative bacilli from community infections at seven centers in the People's Republic of China is reported. The rates of resistance of 1,615 isolates of the family Enterobacteriaceae were as follows: 40.8% for ciprofloxacin, 32.2% for gentamicin, 0% for imipenem or ertapenem, and 14.7% for cefotaxime. The rates of extended-spectrum β-lactamase production were 16% for Escherichia coli and 17% for Klebsiella.

scholarly journals Detecting distant relatives of mammalian LPS-binding and lipid transport proteins

1998 ◽  
Vol 7 (7) ◽  
pp. 1643-1646 ◽  
Author(s):  
Lesa J. Beamer ◽  
Daniel Fischer ◽  
David Eisenberg
Keyword(s):  
Transport Proteins ◽  
Lipid Transport ◽  
Lps Binding

scholarly journals Thrombin-Derived Peptides Potentiate the Activity of Gram-Positive-Specific Antibiotics against Gram-Negative Bacteria

Molecules ◽  
2021 ◽  
Vol 26 (7) ◽  
pp. 1954
Author(s):  
Charlotte M. J. Wesseling ◽  
Thomas M. Wood ◽  
Kristine Bertheussen ◽  
Samantha Lok ◽  
Nathaniel I. Martin
Keyword(s):  
Antibiotic Resistance ◽  
Outer Membrane ◽  
Therapeutic Range ◽  
Structural Features ◽  
Gram Negative Bacteria ◽  
Binding Properties ◽  
Gram Positive ◽  
Gram Negative ◽  
Recent Attention ◽  
Lps Binding

The continued rise of antibiotic resistance threatens to undermine the utility of the world’s current antibiotic arsenal. This problem is particularly troubling when it comes to Gram-negative pathogens for which there are inherently fewer antibiotics available. To address this challenge, recent attention has been focused on finding compounds capable of disrupting the Gram-negative outer membrane as a means of potentiating otherwise Gram-positive-specific antibiotics. In this regard, agents capable of binding to the lipopolysaccharide (LPS) present in the Gram-negative outer membrane are of particular interest as synergists. Recently, thrombin-derived C-terminal peptides (TCPs) were reported to exhibit unique LPS-binding properties. We here describe investigations establishing the capacity of TCPs to act as synergists with the antibiotics erythromycin, rifampicin, novobiocin, and vancomycin against multiple Gram-negative strains including polymyxin-resistant clinical isolates. We further assessed the structural features most important for the observed synergy and characterized the outer membrane permeabilizing activity of the most potent synergists. Our investigations highlight the potential for such peptides in expanding the therapeutic range of antibiotics typically only used to treat Gram-positive infections.

scholarly journals Boar Semen Contamination: Identification of Gram-Negative Bacteria and Antimicrobial Resistance Profile

Animals ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 43
Author(s):  
Luminita Costinar ◽  
Viorel Herman ◽  
Elena Pitoiu ◽  
Ionica Iancu ◽  
Janos Degi ◽  
...  
Keyword(s):  
Antimicrobial Resistance ◽  
Artificial Insemination ◽  
Bacterial Contamination ◽  
Bacterial Species ◽  
Reproductive Capacity ◽  
Gram Negative Bacteria ◽  
Gram Negative ◽  
The Family ◽  
Boar Semen

Bacterial contamination of boar semen occurs with some frequency in artificial insemination centers and may have a negative effect on the quality of the semen as well as on the sows’ reproductive capacity. Normally, the source of bacterial contamination in pig seminal doses is the own boar. However, distilled water or laboratory equipment used to elaborate the seminal doses can be an important source of bacterial contamination. This study focused on the identification of gram-negative bacteria in boar semen, and impact on the quality of ejaculates obtained from boar, as well as on the establishment of antimicrobial resistance patterns of isolated gram-negative bacteria. Semen samples were collected from 96 boars, ranging in age from 12–36 month, from three artificial insemination centers from the North-West of Romania. Bacterial species were identified by two methods: matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry and API 20 E (BioMerieux, France). The main bacteria isolated from the doses diluted semen were gram-negative bacteria (47.91%), with a majority of the contaminant bacteria belonging to the family Enterobacteriaceae: Seratia marcescens 19.56%, Proteus mirabilis 15.21% and Escherichia coli 10.86% and to the family Pseudomonaceae: Ralstonia picketii 17.39%, Burkholderia cepacia 10.86%, Pseudomonas aeruginosa 8.69%, and Pseudomonas fluorescens 4.34%, respectively. More than half of these isolates (56.52%) were resistant to gentamycin and 58.69% were resistant to penicillin. These antibiotics are very frequently added in sperm diluent in the centers for the processing of sperm from boars in Romania. Regular monitoring for bacterial contamination is an important aspect of a control program.

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