The inhibitory effects of glucose and ethanol on Zymomonas mobilis ATCC10988 were isolated through kinetic analysis of transient batch fermentation data. Growth of Z. mobilis was inhibited above a glucose concentration of 80 g/L. Growth was mildly inhibited by ethanol to 50 g/L, and severely inhibited above this concentration. Specific rates of ethanol production and glucose uptake were essentially invariant during batch fermentation. A structured kinetic model was developed, by way of augmentation of the Extended Bottleneck model, to quantify the kinetics of the growth and product formation processes. The model successfully describes the transient batch fermentation of Z. mobilis over a wide range of initial glucose concentration in a semidefined medium.

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Batch fermentations of glucose to ethanol by Z. Mobilis.(ATCC 10988) were examined in several semidefined nutrient media. The measurement of acid produced by the microorganism was used to study its transient fermentation characteristics. Limitation of nitrogen source in the semidefined medium of Rogers and coworkers(2) was found to limit the growth of this microorganism in the late stages of batch fermentations, when the initial glucose concentration was 75 g/L and higher. The microorganism exhibits a preference for inorganic nitrogen over preformed organic nitrogen provided by yeast extract. The microbial growth occurs exponentially in the presence of ammonium sulfate and yeast extract. However, in the absence of ammonium sulfate, the growth occurs in a linear fashion. The "linear" growth phase is characterized by poor cell-mass yields, and during this phase, growth and ethanol production are decoupled. An improved semi-defined growth medium is established which supports better growth rate and cellular yield, without affecting the ethanol yield.

Repeated-butch fermentations of glucose to ethanol by Z . mobilis ( A TCC 10988) were examined in two semi-dejined nutrient media. The measurement of acid produced by the microorganism was used to study its transient .fermentation characteristics. An examination of the inhibitory eject qJ' ethanol in repeatzd-batch fermentations supports an earlier finding on the presence of a 'slow-acting inhibitory mechanism' at high ethanol concentration in Z. mobilis ( A T C C 10988) cultures. The experimental results also suggest that both microbially produced and exogeneously added ethanol have similar inhibitory effects on the fermentation behavior o j this bacterium.

Ovarian cancer patients suffer from high rates of recurrence and mortality. Circulating tumor cells (CTCs) can serve as a minimally invasive tool to improve the clinical management of such cancer patients. Hence there is growing interest in the isolation, characterization and in vitro culture of CTCs. To this end, the porous membrane cell separators developed by MetaCell s.r.o. provide a simple solution. Ovarian cancer cell line models OVCAR3 and SKOV3 were studied by gene expression profiling and immunostaining for the expression of EPCAM, EGFR, HER2, MET and certain other novel therapeutic targets. Cultivation of the cancer cells after their spike recovery from either cell culture medium or from whole blood was explored using MetaCellTM separators. The cells growing on the separator membranes housed in multi-well culture plates was conveniently visualized with vital cell stains. The SKOV3 cells, but not the OVCAR3 cells, were found to migrate through the membrane pores and populate the well bottoms of the culture plates. This can be attributed to the more plastic and invasive nature of SKOV3 cells as characterized by high Vimentin and low EPCAM expression levels. This is akin to the profile exhibited by highly invasive cancer cells that have undergone epithelial to mesenchymal transition (EMT) and that are implicated in the metastatic spread of cancer in patients. Furthermore, the invasive cells growing on the culture plate well bottoms were found to still stain positively for the therapeutic targets of interest. This cultivation device thus offers the ability to selectively interrogate the more invasive sub-populations within the highly heterogeneous CTCs that are typically seen in cancer patients. After the isolation and cultivation of CTCs, if the partitioned invasive cells remain addressable for the therapeutic target under consideration, the patients are more likely to respond to that therapy for the arrest of metastatic disease. In this context, the MetaCellTM separators have the potential to serve as very effective adjunctive aids for the selection and monitoring of ovarian cancer patients for treatment with targeted therapies. Citation Format: Uday K. Veeramallu, M.S. THE CULTIVATION AND PARTITIONING OF INVASIVE OVARIAN CANCER CELLS AFTER THEIR ISOLATION FROM WHOLE BLOOD [abstract]. In: Proceedings of the 11th Biennial Ovarian Cancer Research Symposium; Sep 12-13, 2016; Seattle, WA. Philadelphia (PA): AACR; Clin Cancer Res 2017;23(11 Suppl):Abstract nr TMEM-038.