Antibiotic-resistant Bacterial Pathogens Research Articles

Alpha-bisabolol from brown macroalga Padina gymnospora mitigates biofilm formation and quorum sensing controlled virulence factor production in Serratia marcescens

Biofilm formation, quorum sensing (QS)-regulated virulence and emergence of antibiotic resistance in bacterial pathogens lead to major health problems. In this perspective, antibiofilm agents and QS inhibitors have gained much attention to treat infections caused by antibiotic-resistant pathogens. For the first time, this investigation reports the antibiofilm and QS inhibitory potential of the brown macroalga Padina gymnospora against the nosocomial pathogen Serratia marcescens. The methanolic extract of P. gymnospora inhibited biofilm formation and the production of prodigiosin and protease. Successive solvent extraction, bioassay-guided fractionation of chloroform extract and GC-MS analysis of active fractions showed the presence of alpha-bisabolol with a relative abundance of 69 %. In vitro assays with alpha-bisabolol evidenced the potent inhibition of biofilm and QS-controlled prodigiosin, protease and swarming in S. marcescens, without exerting deleterious effect on its growth and metabolic activity. The results of this study exemplify the use of P. gymnospora and alpha-bisabolol as promising alternatives to antibiotics.

NMR Structures and Interactions of Antimicrobial Peptides with Lipopolysaccharide: Connecting Structures to Functions.

Antimicrobial peptides (AMPs) establish the first line of host defense mechanism against invading microorganisms including bacteria, viruses, fungi and parasites. In recent years, emergence and spread of antibiotic resistance bacterial pathogens have dawn considerable interest in investigations of AMPs. The ability of AMPs to exert lethality against multiple drug-resistant (MDR) bacteria has incited promising avenues for antibiotic development. As a mode of action, most AMPs perturb the membrane organization of bacterial cells. The outer membrane lipopolysaccharide (LPS) of Gram-negative bacteria establishes a superior permeability barrier, in contrast to the peptidoglycan layer of Gram-positive bacteria. Due to LPS barrier, development of antibiotics for drug resistant Gram- negative bacteria are more complicated, with only fewer compounds in the pipeline. Recent studies have demonstrated that LPS actively regulate mode of action of AMPs on the lethality of Gram-negative bacteria. LPS, also known as endotoxin, is the primary agent for septic shock syndromes in intensive care unit killing over 120,000 people in the USA. Currently, anti-sepsis therapies are greatly lacking. Therefore, LPS has been considered as a target for the development of antimicrobial and antisepsis drugs. In recent and past few years, 3-D structures and interactions of a number of AMPs have been determined in complex with LPS micelles. These studies have generated molecular insights towards mode of action and synergistic activity of AMPs in the outer membrane. In this review, atomic resolution structures and interactions of potent AMPs with LPS are discussed providing novel insights of their mode of action.

Suppression of Virulence of Toxigenic Vibrio cholerae by Anethole through the Cyclic AMP (cAMP)-cAMP Receptor Protein Signaling System.

Use of natural compounds as antivirulence drugs could be an alternative therapeutic approach to modify the outcome of bacterial infections, particularly in view of growing resistance to available antimicrobials. Here, we show that sub-bactericidal concentration of anethole, a component of sweet fennel seed, could suppress virulence potential in O1 El Tor biotype strains of toxigenic Vibrio cholerae, the causative agent of the ongoing 7th cholera pandemic. The expression of cholera toxin (CT) and toxin coregulated pilus (TCP), the major virulence factors of V. cholerae, is controlled through a regulatory cascade involving activation of ToxT with synergistic coupling interaction of ToxR/ToxS with TcpP/TcpH. We present evidence that anethole inhibits in vitro expression of CT and TCP in a toxT-dependent but toxR/toxS-independent manner and through repression of tcpP/tcpH, by using bead-ELISA, western blotting and quantitative real-time RT-PCR assays. The cyclic AMP (cAMP)-cAMP receptor protein (CRP) is a well-studied global signaling system in bacterial pathogens, and this complex is known to suppress expression of tcpP/tcpH in V. cholerae. We find that anethole influences the virulence regulatory cascade by over-expressing cyaA and crp genes. Moreover, suppression of toxigenic V. cholerae-mediated fluid accumulation in ligated ileum of rabbit by anethole demonstrates its potentiality as an antivirulence drug candidate against the diseases caused by toxigenic V. cholerae. Taken altogether, these results revealing a mechanism of virulence inhibition in V. cholerae by the natural compound anethole, may have relevance in designing antivirulence compounds, particularly against multiple antibiotic resistant bacterial pathogens.

Isoprenyl caffeate, a major compound in manuka propolis, is a quorum-sensing inhibitor in Chromobacterium violaceum.

The emergence of antibiotic-resistant bacterial pathogens, especially Gram-negative bacteria, has driven investigations into suppressing bacterial virulence via quorum sensing (QS) inhibition strategies instead of bactericidal and bacteriostatic approaches. Here, we investigated several bee products for potential compound(s) that exhibit significant QS inhibitory (QSI) properties at the phenotypic and molecular levels in Chromobacterium violaceum ATCC 12472 as a model organism. Manuka propolis produced the strongest violacein inhibition on C. violaceum lawn agar, while bee pollen had no detectable QSI activity and honey had bactericidal activity. Fractionated manuka propolis (pooled fraction 5 or PF5) exhibited the largest violacein inhibition zone (24.5 ± 2.5 mm) at 1 mg dry weight per disc. In C. violaceum liquid cultures, at least 450 µg/ml of manuka propolis PF5 completely inhibited violacein production. Gene expression studies of the vioABCDE operon, involved in violacein biosynthesis, showed significant (≥two-fold) down-regulation of vioA, vioD and vioE in response to manuka propolis PF5. A potential QSI compound identified in manuka propolis PF5 is a hydroxycinnamic acid-derivative, isoprenyl caffeate, with a [M-H] of 247. Complete violacein inhibition in C. violaceum liquid cultures was achieved with at least 50 µg/ml of commercial isoprenyl caffeate. In silico docking experiments suggest that isoprenyl caffeate may act as an inhibitor of the violacein biosynthetic pathway by acting as a competitor for the FAD-binding pockets of VioD and VioA. Further studies on these compounds are warranted toward the development of anti-pathogenic drugs as adjuvants to conventional antibiotic treatments, especially in antibiotic-resistant bacterial infections.

Botanical alternatives to antibiotics for use in organic poultry production

The development of antibiotic resistant pathogens has resulted from the use of sub-therapeutic concentrations of antibiotics delivered in poultry feed. Furthermore, there are a number of consumer concerns regarding the use of antibiotics in food animals including residue contamination of poultry products and antibiotic resistant bacterial pathogens. These issues have resulted in recommendations to reduce the use of antibiotics as growth promoters in livestock in the United States. Unlike conventional production, organic systems are not permitted to use antibiotics. Thus, both conventional and organic poultry production need alternative methods to improve growth and performance of poultry. Herbs, spices, and various other plant extracts are being evaluated as alternatives to antibiotics and some do have growth promoting effects, antimicrobial properties, and other health-related benefits. This review aims to provide an overview of herbs, spices, and plant extracts, currently defined as phytobiotics as potential feed additives.

Multidrug resistant and carbapenemase producing Enterobacteriaceae among patients with urinary tract infection at referral Hospital, Northwest Ethiopia.

BackgroundUpdates on the epidemiology of antibiotic resistance bacterial pathogens is important. This is because the spread of multidrug resistant enterobacteriaceae (MDRE) and recently carbapenemase producing enterobacteriaceae (CPE) have emerged as a major public health concern in patients with urinary tract infections (UTIs). This study is therefore, aimed to assess the prevalence and associated risk factors of MDR and CPE among patients with UTIs.MethodsA cross sectional study was conducted among 442 symptomatic UTI suspected patients. Data on socio-demographic characteristics, clinical information and possible risk factors were collected using structured questionnaire. Early morning mid-stream urine samples were collected and processed to characterize bacterial isolates. Disk diffusion method was used to determine the antibiotic susceptibility patterns of isolates. Carbapenemase producing strains were detected using CHROMagar KPC medium. Data were entered and analyzed using SPSS version 20. P-value <0.05 was considered as statistical significant.ResultsAmong 442 patients enrolled a total of 183 Enterobacteriaceae were recovered. Of these isolates; 160 (87.4%) were MDRE; the most common isolates were K. pneumoniae and E.coli. Five (2.73%) of the isolates were found to be carbapenemase producers and all of CPE strains were 100% ESBL producers. Significant drug resistances were observed among CPE compared to other MDRE, low resistance rates were noted to ciprofloxacin (20%). Being female (OR 4.46; P = 0.018), age (OR 1.08; P = 0.001), hospitalization (OR 5.23; P = 0.006), and prior antibiotic use (OR 3.98; P = 0.04) were associated risk factors for MDRE.Conclusion and recommendationHigh rates of MDR (87.4%) were observed among enterobacteriaceae uropathogens; K. pneumoniae and E.coli were the principal MDR isolates. Overall prevalence of CPE was 2.73% and all of these strains were 100% ESBL producer. Attributing risk factors for MDR UTIs were found to be sex (female), age, hospitalization, and history of antibiotic therapy. Therefore, efforts should be made to reduce patient hospital stay and maximize rational use of drugs. Additional and vigorous investigation especially on CPE should be encouraged.

Antimicrobial Peptides Derived from Fusion Peptides of Influenza A Viruses, a Promising Approach to Designing Potent Antimicrobial Agents.

The emergence and dissemination of antibiotic-resistant bacterial pathogens have spurred the urgent need to develop novel antimicrobial agents with different mode of action. In this respect, we turned several fusogenic peptides (FPs) derived from the hemagglutinin glycoproteins (HAs) of IAV into potent antibacterials by replacing the negatively or neutrally charged residues of FPs with positively charged lysines. Their antibacterial activities were evaluated by testing the MICs against a panel of bacterial strains including S.aureus, S.mutans, P.aeruginosa, and E.coli. The results showed that peptides HA-FP-1, HA-FP-2-1, and HA-FP-3-1 were effective against both Gram-positive and Gram-negative bacteria with MICs ranging from 1.9 to 16.0μm, while the toxicities toward mammalian cells were low. In addition, the mode of action and the secondary structure of these peptides were also discussed. These data not only provide several potent peptides displaying promising potential in development as broad antimicrobial agents, but also present a useful strategy in designing new antimicrobial agents.

Phage Immobilized Antibacterial Silica Nanoplatform: Application against Bacterial Infections

Antibiotic resistance in bacterial pathogens has become a worldwide public health problem in veteri- nary and human medicine. The emergence of methicillin resistance in Staphylococcus sp. has led to complications in treatment of bovine mastitis, wound infections in horses, dogs, pigs etc. and bacterimia in humans ranging from postules, sepsis to even death. To address this problem of antibiotic resistance, several attempts are being made of which, phage therapy offers a promising alternative. Herein, we report a phage based antibacterial nanoplatform hav- ing bactericidal potential against an isolated methicillin resistant skin bacterium, Staphylococcus arlettae as a model organism. The bacteriophages (phages) used in the study were isolated from sewage water via enrichment method against an isolated methicillin resitant skin bacterium, Staphylococcus arlettae (GenBank accession no. KF589201.1). The isolated phages were characterized thereafter for their host specificity and morphology by plaque assay and transmission electron microscopy (TEM) respectively. Intrinsic charge characteristic of phages was utilized for their immobilization on silica NPs monolyer using different conjugation chemistry, through covalent/electrostatic/ phy- sisorption interactions. The efficacy of each immobilization approach was compared using plaque assay. Silica NPs of size ~ 300 nm were synthesized by hydrolysis and condensation of tetraethylorthosilicate in an alkaline envi- ronment, and characterized using scanning electron microscopy (SEM). The particles were dispersed at air/water interface for monolayer formation on polyvinyllidine fluoride (PVDF) membrane via Langmuir-Blodgett (LB) thin film deposition technique at 15 mN/m surface pressure. It was observed that 3-aminopropyltrimethoxysilane (APTMS) treated membranes act as a better bactericidal platform due to proper orientation of phages by means of electrostatic and covalent interaction as compared to phage bound by physical adsorption. Moreoever, high sur- face/volume ratio of NPs further helped in improving bactericidal performance, associated with large loading ca- pacity of phages on film. Thus, the present study can facilitate in design and development of an effective anti-bac- terial compositions and dressings in veterinary medicine and animal agriculture to combat Staphylococcal infections.

Chemical composition and disruption of quorum sensing signaling in geographically diverse United States propolis.

Propolis or bee glue has been used for centuries for various purposes and is especially important in human health due to many of its biological and pharmacological properties. In this work we showed quorum sensing inhibitory (QSI) activity of ten geographically distinct propolis samples from the United States using the acyl-homoserine lactone- (AHL-) dependent Chromobacterium violaceum strain CV026. Based on GC-MS chemical profiling the propolis samples can be classified into several groups that are as follows: (1) rich in cinnamic acid derivatives, (2) rich in flavonoids, and (3) rich in triterpenes. An in-depth analysis of the propolis from North Carolina led to the isolation and identification of a triterpenic acid that was recently isolated from Hondurian propolis (Central America) and ethyl ether of p-coumaric alcohol not previously identified in bee propolis. QSI activity was also observed in the second group US propolis samples which contained the flavonoid pinocembrin in addition to other flavonoid compounds. The discovery of compounds that are involved in QSI activity has the potential to facilitate studies that may lead to the development of antivirulence therapies that can be complementary and/or alternative treatments against antibiotic resistant bacterial pathogens and/or emerging pathogens that have yet to be identified.

Environmental Factors Influencing Antibiotic Resistant Bacterial Pathogens in Polluted Lake Manzala, Egypt

Lake Manzala is considered one of the most important Costal lakes, in the northern part of Egypt. It suffers from high load of pollutants from different sources such as sewage, industrial and agricultural wastes. In this study, physicochemical characterization of lake water revealed high levels of pollution in different sampling sites such as, pH, TSS, TDS, ammonia, nitrates, sulfates, alkalinity, chlorides, calcium and magnesium. Bacterial count such as TVB and fecal coliform of water and fishes of the lake revealed high contamination in Lake Manzala, a total of 90 isolates were identified and resulted in different bacterial pathogens such as, E. coli, Proteus mirabilis, Sphomonas paucimobilis, Citrobacter freunii, Erwinia sp., Pasturella sp. and Pseudomonas sp. Antibiogram was done for all isolates using eight antibiotics such as penicillin, ampicillin, cefotaxime, chloramphenicol, rifampin, tetracycline, streptomycin and gentamicin. The result showed a high resistant pattern among different species which are harboring plasmid DNA. This is an indication that these bacterial pathogens have risk factors in the communities around Lake Manzala.

Prevalence of antibiotic resistance genes and bacterial pathogens in long-term manured greenhouse soils as revealed by metagenomic survey.

Antibiotic resistance genes (ARGs), human pathogenic bacteria (HPB), and HPB carrying ARGs pose a high risk to soil ecology and public health. Here, we used a metagenomic approach to investigate their diversity and abundance in chicken manures and greenhouse soils collected from Guli, Pulangke, and Hushu vegetable bases with different greenhouse planting years in Nanjing, Eastern China. There was a positive correlation between the levels of antibiotics, ARGs, HPB, and HPB carrying ARGs in manures and greenhouse soils. In total, 156.2–5001.4 μg/kg of antibiotic residues, 22 classes of ARGs, 32 HPB species, and 46 species of HPB carrying ARGs were found. The highest relative abundance was tetracycline resistance genes (manures) and multidrug resistance genes (greenhouse soils). The dominant HPB and HPB carrying ARGs in the manures were Bacillus anthracis, Bordetella pertussis, and B. anthracis (sulfonamide resistance gene, sul1), respectively. The corresponding findings in greenhouse soils were Mycobacterium tuberculosis and M. ulcerans, M. tuberculosis (macrolide-lincosamide-streptogramin resistance protein, MLSRP), and B. anthracis (sul1), respectively. Our findings confirmed high levels of antibiotics, ARGs, HPB, and HPB carrying ARGs in the manured greenhouse soils compared with those in the field soils, and their relative abundance increased with the extension of greenhouse planting years.

Activation of the σE-dependent stress pathway by conjugative TraR may anticipate conjugational stress.

Horizontal gene transfer by conjugation plays a major role in bacterial evolution, allowing the acquisition of new traits, such as virulence and resistance to antibacterial agents. With the increased antibiotic resistance in bacterial pathogens, a better understanding of how bacteria modulate conjugation under changing environments and the genetic factors involved is needed. Despite the evolutionary advantages conjugation may confer, the process can be quite stressful for the donor cell. Here, we characterize the ability of TraR, encoded on the episomal F' plasmid, to upregulate the σ(E) extracytoplasmic stress pathway in Escherichia coli. TraR, a DksA homolog, modulates transcription initiation through the secondary channel of RNA polymerase. We show here that TraR activates transcription directly; however, unlike DksA, it does so without using ppGpp as a cofactor. TraR expression can stimulate the σ(E) extracytoplasmic stress response independently of the DegS/RseA signal transduction cascade. In the absence of TraR, bacteria carrying conjugative plasmids become more susceptible to external stress. We propose that TraR increases the concentrations of periplasmic chaperones and proteases by directly activating the transcription of σ(E)-dependent promoters; this increased protein folding capacity may prepare the bacterium to endure the periplasmic stress of sex pilus biosynthesis during mating.

Synergistic anti-inflammatory activity of the antimicrobial peptides human beta-defensin-3 (hBD-3) and cathelicidin (LL-37) in a three-dimensional co-culture model of gingival epithelial cells and fibroblasts.

Given the spread of antibiotic resistance in bacterial pathogens, antimicrobial peptides that can also modulate the immune response may be a novel approach for effectively controlling periodontal infections. In the present study, we used a three-dimensional (3D) co-culture model of gingival epithelial cells and fibroblasts stimulated with Aggregatibacter actinomycetemcomitans lipopolysaccharide (LPS) to investigate the anti-inflammatory properties of human beta-defensin-3 (hBD-3) and cathelicidin (LL-37) and to determine whether these antimicrobial peptides can act in synergy. The 3D co-culture model composed of gingival fibroblasts embedded in a collagen matrix overlaid with gingival epithelial cells had a synergistic effect with respect to the secretion of IL-6 and IL-8 in response to LPS stimulation compared to fibroblasts and epithelial cells alone. The 3D co-culture model was stimulated with non-cytotoxic concentrations of hBD-3 (10 and 20 µM) and LL-37 (0.1 and 0.2 µM) individually and in combination in the presence of A. actinomycetemcomitans LPS. A multiplex ELISA assay was used to quantify the secretion of 41 different cytokines. hBD-3 and LL-37 acted in synergy to reduce the secretion of GRO-alpha, G-CSF, IP-10, IL-6, and MCP-1, but only had an additive effect on reducing the secretion of IL-8 in response to A. actinomycetemcomitans LPS stimulation. The present study showed that hBD-3 acted in synergy with LL-37 to reduce the secretion of cytokines by an LPS-stimulated 3D model of gingival mucosa. This combination of antimicrobial peptides thus shows promising potential as an adjunctive therapy for treating inflammatory periodontitis.

Composition, anti-quorum sensing and antimicrobial activity of essential oils from Lippia alba.

Many Gram-negative pathogens have the ability to produce N-acylhomoserine lactones (AHLs) as signal molecules for quorum sensing (QS). This cell-cell communication system allows them to coordinate gene expression and regulate virulence. Strategies to inhibit QS are promising for the control of infectious diseases or antibiotic resistant bacterial pathogens. The aim of the present study was to evaluate the anti-quorum sensing (anti-QS) and antibacterial potential of five essential oils isolated from Lippia alba on the Tn-5 mutant of Chromobacterium violaceum CV026, and on the growth of the gram-positive bacteria S. aureus ATCC 25923. The anti-QS activity was detected through the inhibition of the QS-controlled violacein pigment production by the sensor bacteria. Results showed that two essential oils from L. alba, one containing the greatest geranial:neral and the other the highest limonene:carvone concentrations, were the most effective QS inhibitors. Both oils also had small effects on cell growth. Moreover, the geranial/neral chemotype oil also produced the maximum zone of growth inhibition against S. aureus ATCC 25923. These data suggest essential oils from L. alba have promising properties as QS modulators, and present antibacterial activity on S. aureus.

A macrophage-stimulating compound from a screen of microbial natural products.

Rising rates of antibiotic resistance in bacterial pathogens is a medical crisis of global concern that necessitates the development of new treatment strategies. We have isolated a natural product with macrophage-stimulating activity from a screen of microbially produced bioactive molecules. Streptazolin increased bacterial killing and elaboration of immunostimulatory cytokines by macrophages in vitro. Furthermore, we show that streptazolin stimulates the macrophage nuclear factor κB (NF-κB) pathway via phosphatidylinositide 3-kinase (PI3K) signaling, and that the conjugated diene moiety is essential for stimulatory activity. Immunostimulatory molecules like streptazolin represent entries into new treatment paradigms to address the challenge of antibiotic resistance.

Inhibition of co-colonizing cystic fibrosis-associated pathogens by Pseudomonas aeruginosa and Burkholderia multivorans.

Cystic fibrosis (CF) is a recessive genetic disease characterized by chronic respiratory infections and inflammation causing permanent lung damage. Recurrent infections are caused by Gram-negative antibiotic-resistant bacterial pathogens such as Pseudomonas aeruginosa, Burkholderia cepacia complex (Bcc) and the emerging pathogen genus Pandoraea. In this study, the interactions between co-colonizing CF pathogens were investigated. Both Pandoraea and Bcc elicited potent pro-inflammatory responses that were significantly greater than Ps. aeruginosa. The original aim was to examine whether combinations of pro-inflammatory pathogens would further exacerbate inflammation. In contrast, when these pathogens were colonized in the presence of Ps. aeruginosa the pro-inflammatory response was significantly decreased. Real-time PCR quantification of bacterial DNA from mixed cultures indicated that Ps. aeruginosa significantly inhibited the growth of Burkholderia multivorans, Burkholderia cenocepacia, Pandoraea pulmonicola and Pandoraea apista, which may be a factor in its dominance as a colonizer of CF patients. Ps. aeruginosa cell-free supernatant also suppressed growth of these pathogens, indicating that inhibition was innate rather than a response to the presence of a competitor. Screening of a Ps. aeruginosa mutant library highlighted a role for quorum sensing and pyoverdine biosynthesis genes in the inhibition of B. cenocepacia. Pyoverdine was confirmed to contribute to the inhibition of B. cenocepacia strain J2315. B. multivorans was the only species that could significantly inhibit Ps. aeruginosa growth. B. multivorans also inhibited B. cenocepacia and Pa. apista. In conclusion, both Ps. aeruginosa and B. multivorans are capable of suppressing growth and virulence of co-colonizing CF pathogens.

Assessment of physicochemical properties and antimicrobial activity of biological mud isolated from salt lake in Aran-Bidgol against several antibiotic-resistant bacterial pathogens

Assessment of physicochemical properties and antimicrobial activity of biological mud isolated from salt lake in Aran-Bidgol against several antibiotic-resistant bacterial pathogens

Broad-spectrum bug biofilm buster

Biofilms![Figure][1] The deadly pathogen Staphylococcus aureus . PHOTO: DAVID M. PHILLIPS/SCIENCE SOURCE Imagine slime growing on your heart valves. Such infections, which happen all too often and are often deadly, can be eradicated by blocking stress responses in biofilm-producing bacteria—that is, fighting the bacteria's defenses. Unfortunately, however, there are no approved biofilm-busting drugs yet, so Fuente-Nunez et al. went looking for one. They knew that small positively charged synthetic peptides can stop biofilm formation in many antibiotic-resistant bacterial pathogens, such as Staphylococcus aureus, Escherichia coli , and Salmonella . When they performed a screening assay of small peptides, they found a candidate that acts on an important stress pathway. Bacteria use the pathway to synthesize the signaling nucleotide ppGpp. Without ppGpp, the bacteria have trouble forming biofilms and even staying alive. The candidate, peptide 1018, binds directly to ppGpp and degrades it, stopping deadly pathogens in their tracks. PLOS Biol. 10, e1004152 (2014). [1]: pending:yes

Microbial quality and antibiotic resistant bacterial pathogens isolated from groundwater used by residents of Ongata Rongai, Kajiado North County, Kenya

Groundwater represents an important source of drinking water and its quality is currently threatened by a combination of over-abstraction and microbiological and chemical contamination. Nairobi, Kenya and its environs is plagued with un-planned dwelling residential settlements, with limited potable water sources which are often contaminated by bacterial pathogens. This coupled with increased incidences of antibiotic resistance among the pathogens is alarming. This study used the MPN technique to determine indicator organisms, and the agar diffusion method to determine resistance in isolated pathogenic bacteria. The total coliforms values recorded were as high as 1.12x102 (±8.8x101) MPN/100 ml, fecal coliform loads were 8.63(±7.01) MPN/100 ml for the shopping centre. Total bacterial counts values recorded were as high as 5.64x104 (±1.77x104) CFU/ml at the shopping centre. Numerous organisms that are potential enteric pathogens such as Vibrio sp, Salmonella sp., Shigella sp., P. aeruginosa and E. coli were isolated from the water samples. There was high resistance to many antibiotics particularly sulphamoxazole (98.5%), kanamycin (95.3%) and ampicillin (87.5%). The most active antibiotics were chloramphenicol with resistance level of 45.4% and streptomycin (59.4%). The study indicates that water from the studied boreholes was not suitable for human consumption and therefore calls for urgent intervention. There is a high likelihood that congestion and lack of proper waste and waste water management is responsible for contamination of aquifers in this region.Keywords: groundwater, contamination, coliforms, potable water, antibiotic resistance

Genesis of antibiotic resistance VI: monitoring of water quality for antibiotics, its metabolic breakdown products in the Texas Clean Rivers Program by the Texas Commission on Environmental Quality and also by the Texas Water Development Board (986.6)

Established in 1991, the Texas Clean Rivers Program (CRP) is a non‐profit regulatory program for managing and/or monitoring water quality issues at the watershed level, within the river basins in Texas. A systematic data query for antibiotics, their metabolic breakdown products (Chemical intermediates, Parent ‐ Daughter Transition Compounds), and antibiotic resistant bacterial pathogens on surface water quality monitoring database [http://www.tceq.texas.gov/waterquality/clean‐rivers/data/samplequery.html], collected under a TCEQ‐approved quality assurance, conforms to the provisions of NELAP (National Environmental Laboratory Accreditation Program, July 2008). Storet queries for “Antibiotics” “Metabolic breakdown products of Antibiotics” , “Antibiotic Resistant bacterial pathogens”, and Antibiotic Resistant bacterial pathogens in fish tissues”, in the data base: http://www.tceq.texas.gov/waterquality/clean‐rivers/data/storet.html for the period of 2000 ‐ 2012 shows no data on file for said queries. Similar data queries in the TWDB database at http://www.twdb.texas.gov/groundwater/data/index.asp shows no data on file. The implication on lack information or scant information on said quires, and also most recent theoretical projections on “Antibiotic Resistance in the United States in 2013 by Center for Disease Control and Prevention is a serious public health concerns. Lack of data analysis from the Water Quality data supporting the CDC&amp;P claims shall be presented in the Experimental Biology of 2014. Grant Funding Source: Professional Developement Funds from SWTJC, Eagle Pass