To the biology of gonococcus

Nagell and Danielsen (Derm. Ztsch. Bd. 56, H. 1, 29), on the basis of five-year observations, consider gonococcs to be strictly gram-negative, pathogenic only to humans. Gonococci are peculiar to various sugars (ferment glucose). Finally, after testing the preparation Gonovitan (the preparation was recently proposed in Germany as containing live gonococcs and recommended by a number of doctors for use. Ref.), We found that Gonovitan No. 1, 81 contained a culture of micrococcus cat., No. 82 is a closely related species of microbe to micr. cat. and No. 100 contained Lingelsheim's diplococcus muc. The authors do not recommend using the vaccine with "live gonococcs" as it does not contain the named type of microbe.

TEST THE ABILITY OF SEDIMENT BACTERIA ISOLATES IN DEGRADATING PHENOL

Phenol degrading bacteria can be found in various habitats in marine environments. This study aims to obtain bacteria from sediments that are able to degrade phenol. The process of bacterial purification and degradation was carried out from August to September 2018 at the Marine Microbiology Laboratory, Department of Marine Sciences, Faculty of Fisheries and Marine, University of Riau. Analysis of the reduction in phenol concentration was carried out using the APHA 5530 method using UV-VIS spectrophotometry conducted at the Health and Environment Laboratory. The bacterial isolates used as test bacteria were isolates BF1A, BF4B and BF9C. Bacterial and biochemical tests were carried out for all bacterial isolates. Two isolated showed mehyl red negative, all isolates were motile. Three isolates were positive catalase, able to ferment glucose and sucrose fermented citrate and two isolat were Gram negative bacterial. The three bacterial isolates were able to degrade phenol with the highest degradation for 1ppm shown in isolates BF1A, the highest degradation of concentrations of 2 ppm and 3 ppm was shown in isolates BF9C. Thus, the isolat BF9C was able to degrade the highest phenol.

Saccharomyces cerevisiae displays an increased growth rate and an extended replicative lifespan when grown under respiratory conditions in the presence of bacteria

Individual cells of the budding yeast Saccharomyces cerevisiae have a limited replicative potential, referred to as the replicative lifespan. We have found that both the growth rate and average replicative lifespan of S. cerevisiae cells are greatly increased in the presence of a variety of bacteria. The growth and lifespan effects are not observable when yeast are allowed to ferment glucose but are only notable on solid media when yeast are forced to respire due to the lack of a fermentable carbon source. Growth near strains of Escherichia coli containing deletions of genes needed for the production of compounds used for quorum sensing or for the production of the siderophore enterobactin also still induced the lifespan extension in yeast. Furthermore, the bacterially induced increases in growth rate and lifespan occur even across gaps in the growth medium, indicating that the bacteria are influencing the yeast through the action of a volatile compound.

Carbapenem-Resistant Non-Glucose-Fermenting Gram-Negative Bacilli: the Missing Piece to the Puzzle

The non-glucose-fermenting Gram-negative bacilliPseudomonas aeruginosaandAcinetobacter baumanniiare increasingly acquiring carbapenem resistance. Given their intrinsic antibiotic resistance, this can cause extremely difficult-to-treat infections. Additionally, resistance gene transfer can occur between Gram-negative species, regardless of their ability to ferment glucose. Thus, the acquisition of carbapenemase genes by these organisms increases the risk of carbapenemase spread in general. Ultimately, infection control practitioners and clinical microbiologists need to work together to determine the risk carried by carbapenem-resistant non-glucose-fermenting Gram-negative bacilli (CR-NF) in their institution and what methods should be considered for surveillance and detection of CR-NF.

Isolation and Identification ofAcholeplasmasp. from the Mud Crab,Scylla serrata

For the first time, a mollicute-like organism (MLO) was cultured from moribund mud crabs (Scylla serrata) during an outbreak of clearwater disease in Zhejiang Province, China. The MLO displayed a fried-egg colony morphology in culture, did not possess a cell wall, and was not retained by 0.45 μm and 0.2 μm filters. It was able to ferment glucose, sucrose, lactose, and maltose, but it did not utilize arginine and urea. The MLO grew in the absence of bovine serum and was not susceptible to digitonin. Sequence analysis of the 16S rRNA gene revealed that this MLO had 99% identity withAcholeplasma laidlawiiPG-8A, which indicates that the organism isolated from mud crabs is a member of the genusAcholeplasma.

Improved Succinic Acid Production in the Anaerobic Culture of an Escherichia coli pflB ldhA Double Mutant as a Result of Enhanced Anaplerotic Activities in the Preceding Aerobic Culture

ABSTRACT Escherichia coli NZN111 is a pflB ldhA double mutant which loses its ability to ferment glucose anaerobically due to redox imbalance. In this study, two-stage culture of NZN111 was carried out for succinic acid production. It was found that when NZN111 was aerobically cultured on acetate, it regained the ability to ferment glucose with succinic acid as the major product in subsequent anaerobic culture. In two-stage culture carried out in flasks, succinic acid was produced at a level of 11.26 g/liter from 13.4 g/liter of glucose with a succinic acid yield of 1.28 mol/mol glucose and a productivity of 1.13 g/liter·h in the anaerobic stage. Analyses of key enzyme activities revealed that the activities of isocitrate lyase, malate dehydrogenase, malic enzyme, and phosphoenolpyruvate (PEP) carboxykinase were greatly enhanced while those of pyruvate kinase and PEP carboxylase were reduced in the acetate-grown cells. The two-stage culture was also performed in a 5-liter fermentor without separating the acetate-grown NZN111 cells from spent medium. The overall yield and concentration of succinic acid reached 1.13 mol/mol glucose and 28.2 g/liter, respectively, but the productivity of succinic acid in the anaerobic stage dropped to 0.7 g/liter·h due to cell autolysis and reduced anaplerotic activities. The results indicate the great potential to take advantage of cellular regulation mechanisms for improvement of succinic acid production by a metabolically engineered E. coli strain.

Mycoplasma verecundum, a New Species Isolated from Bovine Eyes

Summary: Two similar micro-organisms with the characteristics of the order Mycoplas-matales were isolated from the eyes of calves with conjunctivitis. Both isolates produced only a slight pH decrease in broth and did not ferment glucose or hydrolyse arginine or urea -- hence they were almost undetectable by fluid cultures. Other biological characters included sterol dependence, indicative of the genus Mycoplasma, production of film and spots, growth at low temperature (20°C) or low pH (4.7), and failure to reduce tetrazolium. The two strains were serologically indistinguishable from each other, but distinct from known bovine and other Mycoplasma species tested. Because of their distinct biological and serological characteristics they are proposed as forming a separate new species, Mycoplasma verecundum, with strain 107 (nctc10145) as the type strain.

Fructooligosaccharide Utilization by Salmonellae† and Potential Direct-Fed-Microbial Bacteria for Poultry

Experiments were done to characterize potential direct-fed-microbial (DFM) bacteria for poultry and Salmonella spp. with respect to their abilities to metabolize fructooligosaccharide substrates (FOS-50® or pure FOS). Oxygen uptake (QO2) by these bacteria in media containing either glucose, FOS-50®, or FOS was determined with a Warburg respirometer. QO2 values for Salmonella spp. In media containing glucose or FOS-50® were similar(P >0.05); however, QO2 values in medium with FOS were significantly lower (P <0.05).The QO2 values for Enterococcus faecium, Lactococcus lactis, and Pediococcus sp. were considerably lower, reflecting the inability of these bacteria to oxidatively utilize these carbohydrates. The ability of E. faecium, L. lactis, and Pediococcus sp. to ferment glucose, FOS-50®, or FOS was determined by measuring pH changes of the media. All carbohydrate sources were fermented by these bacteria, but at different rates. The lowest pH values (<4.6) were obtained in inoculated media supplemented with glucose. The highest fermentation rate was achieved by Pediococcus sp. (pH< 5.2 at 7h), while L. lactis showed the slowest fermentation rate (pH > 6.4 at 10 h). To test the ability of Pediococcus sp. to hydrolyze FOS substrates, a cell-free extract was spectrophotometrically analyzed for the presence of active enzymes capable of hydrolyzing FOS or sucrose (a component of FOS). Hydrolysis of FOS (release of glucose) but not of sucrose was evident. However, equal activity was found in aqueous FOS without the cell-free extract, which suggests that free glucose was a component of the FOS solution tested.

Anaerobic Removal of Chlorate from Bleach Effluents

Anaerobic biological removal of chlorate was studied on a laboratory and pilot plant scale. Continuous laboratory tests in an anaerobic fixed-film process showed that chlorate can be removed completely from kraft bleach effluent at such a short hydraulic retention time as 0.6 h. The efficiency of biological chlorate removal was confirmed under practical conditions in a 20 m3 pilot plant, operating at a Swedish craft mill. Four chlorate reducing bacterial strains were isolated and characterized. All four isolates were gram-negative, catalase- and oxidase-positive, motile rods. None of the four isolates could ferment glucose, while they could all grow aerobically and with nitrate as electron acceptor.

Ethanol production by a newly isolated anaerobe, Clostridium saccharolyticum: effects of culture medium and growth conditions

Clostridium saccharolyticum was shown to ferment glucose, cellobiose, and xylose to CO2, H2, ethanol, acetate, and lactate. The addition of 0.12 M CaCO3 and 1% yeast extract (w/v) to the glucose medium was found to shift the ethanol–acetate mole ratio from 1.36 to 2.6. Although the addition of exogenous H2 (240 kPa) did not affect the growth of C. saccharolyticum, it did alter the pattern of fermentation products. Both H2 and acetate formation decreased, while ethanol production increased. Ethanol production also increased at the expense of H2 and acetate when C. saccharolyticum was incubated without shaking. Stationary incubation under a H2 headspace (standard temperature and pressure) resulted in an ethanol concentration, at 25 °C, of 1.7% (v/v), an efficiency of conversion of 1.8 mol ethanol/mol glucose, and ethanol–acetate ratios of 7.6 at 35 °C and 9.4 at 20 °C. These results indicate that H2 concentration plays a significant role in the regulation of C. saccharolyticum catabolism.