Background: Escherichia coli cause mammary gland inflammation in dairy cows with striking local and sometimes severe systemic clinical symptoms. This disease affects many high producing cows in dairy herds and may cause several cases of death per year in the most severe cases. The present study was planned to evaluate the antibiogram and virulence factors of the isolated bacteria responsible for mastitis.&nbsp; 
 
Methods: In this study, 300 milk samples were collected and subjected to identify clinical mastitis (based on clinical symptoms) and sub clinical mastitis (using California mastitis test). E. coli was isolated and identified from mastitis positive samples and further tested for antibiogram and virulence factors such as haemolysis, biofilm formation and fimH and pap genes presence. 
 
Result: Out of 300 milk samples collected, 121 (40.33%) were positive for mastitis. E. coli was isolated from only 30 (24.79%) out of 121 mastitis positive samples. On Serotyping for somatic antigen, 13 E. coli isolates belonged to somatic serogroup O83, 2 to O157 and one each to O8, O20, O49, O119, O128 and O145. The highest sensitivity of E. coli isolates was recorded for ciprofloxacin, followed by gentamicin, tetracycline, nitrofurantoin, chloramphenicol, amikacin, cefixime, trimethoprim, ampicillin/sulbactam, ceftriaxone, cefoperazone, cefotaxime, kanamycin, cefotaxime/clavulanic acid and amoxycillin in the decreasing order. Multidrug resistance (MDR) was recorded in 96.66% of isolates.&nbsp;Out of 30 E. coli isolates, 46.66% were haemolytic and 40.0% positive for Congo red dye binding. Biofilm production was shown by 76.66% isolates. Molecular characterization revealed presence of fimH gene in 9 isolates, but pap gene was not detected in any of the strain. It may be concluded that E. coli is an emerging environmental mastitogen in cows and isolation of MDR strains with virulence factors is of serious concern.

Antibiogram, Haemolysis and Biofilm Properties of Escherichia coli from Bovine Mastitis

Diarrhoea in canines is mainly caused by Escherichia coli which can be fatal also. To understand the depth of this infection, a study was undertaken to detect E. coli isolates from diarrhoeic and non-diarrhoeic dogs in Southern part of West Bengal. A total of 112 canine samples were tested during May to September 2012 revealing approx 63.4% (71) samples positive for Escherichia coli. The most common serotypes were O8 (23.9%) followed by O157 (19.7%), O101 (16.9%), O26 (15.5%), O153 (12.7%) and O6 (11.3%). Among these O6, O8, O26 and O157 were highly pathogenic to mice causing almost 100% mortality within 24hrs of inoculation and were also detected to be haemolytic on sheep blood agar plates except serotype O8. These isolates were mostly sensitive to nalidixic acid (80.29%), cotrimoxazole (78.88%), ciprofloxacin (74.65%), colistin and ceftriaxone (both 71.83%) but were resistant to amikacin (97.18%), kanamycin (95.78%), cephalexin (92.96%) and enrofloxacin (84.51%).

Characterization and antibiogram of enteropathogenic Escherichia coli isolated from diarrhoeic and non-diarrhoeic dogs in South Bengal, India

<div>Background: Cephalosporins are major antimicrobials used to treat serious infections. However, their effectiveness is being compromised by the emergence of extended spectrum beta lactamases (ESBL). The present study was aimed to characterize ESBL producing Escherichia coli from healthy and diarrheic cattle calves. 
&nbsp; 
Methods: A total of 52 rectal swabs were collected from healthy and diarrheic cattle calves between August 2019 to March 2020. Phenotypically E. coli were characterized based on morphology, microscopy and biochemical tests. Extended Spectrum Beta Lactamases (ESBL) E. coli initial screening was performed by using cefpodoxime, ceftazidime, cefepime and aztreonam antibiotics. The confirmation of the ESBL producing strains was conducted through ESBL phenotypic identification kit and double disc diffusion test (DDDT). Molecular characterization of ESBL E. coli was conducted by PCR amplification of blaCTX-M, bla TEM and bla AmpC genes. Plasmid profiling of the ESBL E. coli isolates was carried out. 
&nbsp; 
Result: Phenotypically, out of the 51 E. coli isolated, 05 (9.8%) E. coli isolates were confirmed as ESBL strains. PCR amplification revealed 01 (20%), 04 (80%) and 03 (60%) isolates positive for blaCTX-M, bla TEM and bla AmpC genes, respectively. Plasmid profiling of the isolates showed that 60% isolates were harboring plasmids of varying size and number. The plasmid number among the isolates ranged from 0-4 plasmids per isolate and plasmid size varied from 900bp to &gt;10kb. The relatively high rates of ESBL producers in diarrheic calves were found than healthy calves. The study highlights the existence of ESBL producing E. coli isolates with certain strains carrying mobile genetic elements in livestock and probable disseminators of resistance, thus imposing public health threat. 
&nbsp;</div>

Characterization of Extended Spectrum Beta Lactamase Producing Escherichia coli from Calves

<div style="text-align: justify;">The present study was carried out for isolation and molecular characterization of Escherichia coli from faecal and meat samples of food animals viz. cattle, pigs and poultry. A total of 66 E. coli isolates were recovered from 420 samples of different food animals and further confirmed by PCR targeting E. coli specific uidA gene. These isolates were sensitive to chloramphenicol and ciprofloxacin and resistant to ampicillin and cloxacillin. Out of 66 isolates, 42 were typed into 13 different &lsquo;O&rsquo; serogroups, 13 untypable and remaining 11 were identified as rough. Serogroup O84, O101, O118, O120 and O147 were predominant and serogroup O118 was found to be common in the samples of all 3 species of food animals. Five (7.57%) and 3 (4.54%) of E. coli isolates were found to harbor virulent genes, stx2 and est, respectively. Twenty representative E. coli isolates selected randomly from 20 different locations were subjected to molecular typing by PCR targeting Repetitive Extragenic Palindromic (REP) sequences. The region specific molecular types of E. coli could not be detected by using REP-PCR based discrimination.</div>

<div style="text-align: justify;">Molecular Characterization of Escherichia Coli Isolates from Food Animals</div>

<div>Background: Multi-drug resistant Escherichia coli (E. coli) can cause a variety of diseases that lead to considerable economic losses in the swine industry. In the past, the mainstream view believed that most bacterial resistance was caused by planktonic bacteria, but the ability of bacteria to form biofilms was ignored. Here, we isolated and identified 185 strains of E. coli from pigs in central China and analyzed the relationship between their genetics, antibiotic sensitivity and biofilm formation ability. 
 
Methods: First, the isolates were classified according to biofilm formation ability by semi-quantitative staining of crystal violet. Then, Phylogenetic group analysis of isolates by polymerase chain reaction. In addition, E. coli with different biofilm-forming abilities were evaluated for antimicrobial susceptibility in its planktonic and biofilm state. Finally, the drug resistance pattern of the isolates with different biofilm formation capabilities were compared. 
 
Result: most of the collected strains showed biofilm formation ability (87.57%, 162/185). The isolated E. coli with biofilm formation ability were classified into the following groups: A (16.05%, 26/162), B1 (10.49%, 17/162), B2 (33.33%, 54/162) and D (40.12%, 65/162). Simultaneously, the isolated E. coli were classified into the following groups according to the biofilm formation ability: Strong (34.57%, 56/162), Moderate (33.33%, 54/162), Weak (32.10%, 52/162) and Absent (12.43%, 23/162). Compared with the planktonic cells, the isolates showed a significant increase in the resistance rate in the biofilm form. And the isolates of the strong biofilm-forming ability group had a high drug resistance pattern. This study provides data of the drug resistance of pig-derived E. coli with different biofilm-forming abilities and provides a scientific basis for guiding veterinary clinical treatment and disease prevention.</div>

<div>Effect of Biofilm Formation on the Escherichia coli Drug Resistance of Isolates from Pigs in Central China</div>

<div>Escherichia coli is the most extensively used organism in recombinant protein production. It has several advantages including a very short life cycle, ease of genetic manipulation and the well-known cell biology etc. which makes E. coli as the perfect host for recombinant protein expression. Despite many advantages, E. coli also have few disadvantages such as coupled transcription and translation and lack of eukaryotic post-translational modifications. These challenges can be overcome by adopting several strategies such as, using different E. coli expression vectors, changing the gene sequence without altering the functional domain, modified E. coli strain usage, changing the culture parameters and co-expression with a molecular chaperone. In this review, we present the level of strategies used to enhance the recombinant protein expression and its stability in E. coli.</div>

<div>Recombinant protein expression optimization in Escherichia coli: A review</div>

<div>Background:&nbsp;Escherichia coli and Klebsiella pneumoniae are two important commensals with pathogenic potentiality in animals and birds, causing intestinal and extra-intestinal infections. These are somewhat zoonotic too via different routes. So, the present study was undertaken to investigate the prevalence of these two bacteria from cloaca and environment of ducks from different districts of West Bengal, followed by detailed characterization and antibiogram. 
 
Methods: Around 197 duck and environmental samples were collected from different districts of West Bengal. E. coli and K. pneumoniae were isolated from collected samples as per standard methods followed by serotyping of the E. coli isolates. The detection of ESBL/ACBL producing isolates was done both phenotypically and genotypically by detecting the presence of antibiotic-resistant genes. Virulence property and biofilm-producing ability of these isolates were also studied. Antibiogram of the ESBL and biofilm positive isolates were done using common 12 antibiotics by disc diffusion method.&nbsp; &nbsp; 
 
Result: A total of 134(68.02%) Escherichia coli and 33(16.75%) Klebsiella pneumoniae isolates were recovered and confirmed by PCR. The prevalence of E. coli and K. pneumoniae in cloacal swabs were less in comparison to the environmental samples (72.09% and 20.93%). Approx. 79.85% E. coli and 72.73% K. pneumoniae isolates were found to be the ESBL/ACBL producers in vitro. E. coli and K. pneumoniae isolates possessed all major antibiotic-resistant genes with the blaAmpC (64.18% &amp; 48.48%) being the most prevalent one. Twenty three (17.16%) E. coli isolates were found positive for the virulence genes, of which stx1 (39.13%) was the most common one as detected by multiplex PCR. No virulence gene was found in K. pneumoniae isolates. Ninety one (67.91%) E. coli and 26(78.79%) K. pneumoniae isolates possessed the biofilm-producing genes. All the ESBL and biofilms producing E. coli and K. pneumoniae isolates showed 100% - 95.24% resistance to ampicillin. A high percentage of resistances were also seen against cefotaxime, ticarcillin/ clavulanic acid, ertapenem, ceftazidime, norfloxacin and ciprofloxacin, which may be due to several reasons. Maximum overall sensitivity was detected against chloramphenicol, co-trimoxazole and gentamicin.</div>

Detection and Characterization of &beta;​-lactamases and Biofilm-producing Escherichia coli and Klebsiella pneumoniae from Ducks and Duck Environments in West Bengal

<div>Background:&nbsp;Staphylococcus aureus (S. aureus), Escherichia coli (E. coli), Trueperella pyogenes (T. pyogenes), Klebsiella pneumoniae (K. pneumoniae), Bacillus&nbsp;spp. and&nbsp;Fusobacterium necrophorum&nbsp;(F. necrophorum) are the common bacterial agents isolated from postpartum endometritis in dairy cattle. The objective of the present study was to determine the association of&nbsp;E. coli&nbsp;with postpartum endometritis by polymerase chain reaction (PCR). 
 
Methods:&nbsp;The present study was conducted from September 2019 to January 2020 at Teaching Veterinary Clinical Complex, College of Veterinary and Animal Sciences, Pookode, Kerala and organised dairy farms in Wayanad district, Kerala. Endometrial cytobrush samples (n = 36) were collected by cytobrush technique at 28 to 35 days postpartum (dpp). 16S rRNA gene was employed for the identification of&nbsp;E. coli&nbsp;by PCR. 
 
Result:&nbsp;Upon evaluating endometrial cytological smear, 26 animals were positive for endometritis with more than 5% polymorphonuclear (PMN) cells. The prevalence of endometritis was 72.22 per cent (26/36).&nbsp;E. coli&nbsp;was detected in 12 samples by PCR. The study suggested PCR as a highly sensitive method for the identification of&nbsp;E. coli&nbsp;associated with endometritis in postpartum dairy cows.</div>

<div>Detection of Escherichia coli in Postpartum Clinical Endometritis of Dairy Cattle by PCR</div>

<div>Background: Bacterial resistance to beta-lactam antibiotics has risen dramatically in Escherichia coli from poultry and other food animals due to the production of extended-spectrum beta-lactamase enzyme (ESBLs) which degrades third generation cephalosporins.Herbs could be a better alternative for such cases.&nbsp; 
 
Methods: Present study was undertaken on 400 caecal samples of healthy broilers, collected from various poultry sale outlets of Jabalpur (M.P.). Samples were screened phenotypically and genotypically for the presence of extended spectrum beta lactamase producing E. coli. Inhibitory effect of fruit peel juice of Punica granatum and Syzigium aromaticum oil observed on the Beta lactamase enzyme obtained from these positive samples by colorimetric method using CENTA and NITROCEFIN as chromogenic substrate. 
 
Result: Phenotypically 135 samples/isolates were ESBL producing E.coli. On multiplex PCR assay 76 positive samples with bla TEM, blaCTX and bla SHV, gene was obtained. Oil of Syzygium aromaticum showed maximium per cent inhibition, Punica granatum depicted lower per cent inhibition with CENTA and NITROCEFIN respectively. Combination of both herbs showed increased inhibition. Tazobactum, (100&micro;M) taken as the standard control exhibited 99.88 and 98 per cent inhibition of ESBL enzyme.</div>

<div>Inhibitory Effect of Herbs on Extended Spectrum Beta Lactamase Enzyme from Escherichia coli of Healthy Broilers</div>

Background: The aim of the research is to detect Extended-Spectrum Beta-Lactamase (ESBL) producing Escherichia coli among chickens, cage swabs and wastewaters from poultry in Indonesia. 
&nbsp; 
Methods: A total of 426 samples were collected, consisting of 200 chicken small intestine contents, 149 cage swabs and 77 wastewater. Isolation and identification of Escherichia coli were carried out on samples, followed by antimicrobial resistance testing using the Kirby-bauer diffusion test method. Phenotypic ESBL confirmation testing uses the double disc synergy test (DDST). 
&nbsp; 
Result: Of the 264 Escherichia coli isolates, 19.3% (n = 51) were confirmed ESBL producers, out of which 58.8% (n = 30) were obtained from ayam and 41.2% (n = 21) from poultry environments. Out of a total of 21 Escherichia coli isolates from poutry environments, 80.9% (n = 17) were from cage swabs and 19.1% (n = 4) from wastewaters. Based on these results, it can be seen that chickens can be considered as a transmission medium for ESBL-producing Escherichia coli and play a role in its spread into the environment which can ultimately pose a risk to public health. Coordinated and appropriate action is needed to reduce its impact now and in the future. 
&nbsp;

Phenotypic Extended-spectrum Beta-lactamase Producing Escherichia coli among Chickens, Cage Swabs and Wastewaters from Poultry in Indonesia