scholarly journals Responses of diverse heterotrophic bacteria to elevated copper concentrations

1994 ◽  
Vol 40 (5) ◽  
pp. 408-411 ◽  
Author(s):  
A. S. Gordon ◽  
L. D. Howell ◽  
V. Harwood

The influence of copper on the growth of Escherichia coli, Pseudomonas aeruginosa, Bacillus cereus, Bacillus subtilis, Vibrio parahaemolyticus, Vibrio alginolyticus (three strains), and an unidentified Vibrio sp. was examined in batch cultures. The effects of copper at micromolar concentrations varied from undetectable to complete growth inhibition. Each strain was able to recover from a growth lag observed after copper addition at a characteristic concentration. Copper concentrations that allowed recovery ranged from 25 to 150 μM. Extracellular proteins in the medium of cultures that had recovered from copper stress were compared with those from control cultures. Protein profiles were analyzed for the presence of proteins similar to extracellular copper-binding proteins (CuBP) previously reported in V. alginolyticus. CuBP-like proteins were found in each Vibrio sp. examined. A protein of similar molecular mass was also detected in copper-stressed cultures of P. aeruginosa and not in control cultures. Escherichia coli and Bacillus spp. did not produce CuBP-like proteins. The data show that CuBP-like proteins are not produced by all bacteria in response to copper stress and indicate that such proteins are common in marine Vibrio spp.Key words: copper toxicity, heterotrophic bacteria, extracellular protein.

1988 ◽  
Vol 66 (2) ◽  
pp. 187-191 ◽  
Author(s):  
Norio Shimizu ◽  
Shinichi Fukuzono ◽  
Kiyoshi Fujimori ◽  
Nabuko Nishimura ◽  
Yoji Odawara

2011 ◽  
Vol 27 (3) ◽  
pp. 883-892
Author(s):  
M.I. Urosevic ◽  
D. Stojanovic ◽  
B. Lako ◽  
I. Jajic ◽  
Z. Milicic ◽  
...  

The research was conducted on 19 stud farms in Serbia, on 80 mares used for breeding, with and without reproductive disorders. During the two years period (from 2009 to 2010) double guarded uterine swabs from 80 mares, aged between 3 and 22 years were collected. Mares belonged to the different breeds: Thoroughbred, Standardbred, Lipizzaner and mixed breeds. It was determined, that bacterial infection of genital organs was found in 24 mares in the examined population, and the bacterial species Streptococcus zooepidemicus was diagnosed in the 11 samples from cervical swabs. In the 5 samples, Escherichia coli was isolated, while Staphylococcus epidermidis and Pasteurella multocida were present in the 2 samples each, while the other causes and simultaneous isolation of two bacterial species are much less present. These species are: Bacillus spp. plus Escherichia coli; Streptococcus zooepidemicus plus Klebsiella pneumoniae and Escherichia coli plus Streptococcus zooepidemicus. In one swab we determinated Arcanobacter pyogenes. In this examination, according to available data after natural mating, we found conception level of 43,10%, which is similar with previous reports in our country.


2021 ◽  
Vol 10 (12) ◽  
pp. e596101220735
Author(s):  
Iara Nunes de Siqueira ◽  
Aline Antas Cordeiro Cavalcanti ◽  
Joyce Galvão de Souza ◽  
Filipe Jordão Pereira de Medeiros ◽  
João Carlos Taveira ◽  
...  

The sanitary evaluation of equipment and hands is fundamental to investigate the presence of pathogens in the dairy industry. Then, this study aims to evaluate the sanitization of equipment, workers’ hands, raw and pasteurized milk in goat milk dairies in the Cariri region, state of Paraíba.  Collected 32 samples of four dairies represented by letters A, B, C, and D. The followings contents were analyzed: mesophiles, total and thermotolerant coliforms, Escherichia coli, Staphylococcus aureus, Samonella spp. and Listeria monocytogenes in the reception tank, pasteurization tank, packing machine, package, wall, workers’ hand, and each dairy’s raw and pasteurized milk. After isolation, 84 colonies were confirmed by MALDI TOF. The indicator microorganisms presented variations for the workers’ hands, while A and B stayed within the patterns. For the equipment, only dairy B was within limits. They were out of the standard for mesophiles, total coliforms, and thermotolerant regarding raw and pasteurized milk. The microorganisms, the Enterobacteriaceae family presented a higher frequency, with 77.38%, and within this family, Escherichia coli, Klebsiella spp., and Enterobacter spp. were the most prevalent. Gram-positive corresponded to 22.62%, Bacillus spp., Staphylococcus spp., Enterococcus spp., and Macrococcus caseolyticus. Listeria monocytogenes and Salmonella spp. were not isolated. These demonstrate failures in goat milk processing with pathogenic bacteria in several dairy plants, indicating the need to adjust the product’s quality control.


2020 ◽  
pp. 11-16
Author(s):  
Adedayo Emmanuel Ogunware ◽  
Odubiyi Opeyemi Esther ◽  
Pelumi Abimbola Adedigba ◽  
Adesewa Adeyinka Adekoya

A total of fifteen pre-packaged fruit salad samples containing pineapple, water melon, pawpaw and cucumber sold in the Lagos State University, Ojo Campus was analyzed using culture techniques for its microbial qualities. Five bacteria genera isolates obtained are Bacillus spp, Staphylococcus aureus, Pseudomonas spp, Escherichia coli, Streptococcus and the three fungi genera isolates are Aspergillus species, Penicillium species, and Saccharomyces cerevisiae. Escherichia coli had the highest frequency of (40%) followed by Streptococcus with (20%), Staphylococcus, Bacillus, Pseudomonas has the same frequency of (13%). The total viable count was in the range of 1.6 × 105 cfu/g to 5.65 × 105 cfu/g while the total coliform count ranged from 1.0 × 105 to 3.3 × 105 cfu/g. The fungal count ranged from 1.5 × 105 to 3.4 × 105 cfu/g. This study revealed that fruit salads in the studied area needs proper sanitation practice during processing in order to avoid risks associated with the consumption of contaminated fruits for the consumers.


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