AIMS Survival of Escherichia coli O157:H7 and nonpathogenic E. coli on spinach leaves and in organic soil while growing spinach in a growth chamber was investigated. METHODS AND RESULTS Spinach plants were maintained in the growth chamber at 20 degrees C (14 h) and 18 degrees C (10 h) settings at 60% relative humidity. Five separate inocula, each containing one strain of E. coli O157:H7 and o...

I was born in Vienna and came to the United States as a refugee in October 1938. This experience played an important role in my view of the world and my approach to science: It contributed to my realization that it was safe to stop working in fields that I felt I understood and to focus on different areas of research by asking questions that would teach me and others something new. I describe m...

The stoichiometry of Photosystem II (PSII) to Photosystem I (PSI) reaction centres in spinach leaf segments was determined by two methods, each capable of being applied to monitor the presence of both photosystems in a given sample. One method was based on a fast electrochromic (EC) signal, which in the millisecond time scale represents a change in the delocalized electric potential difference ...

We propose a novel avenue for state space reduction in time domain Liouville space spin dynamics simulations, using detectability as a selection criterion--only those states that evolve into or affect other detectable states are kept in the simulation. This basis reduction procedure (referred to as destination state screening) is formally exact and can be applied on top of the existing state sp...

Chloroplasts, Compartmental Analysis, Indole-3-acetic Acid (LAA), Spinach Mesophyll Cells, Tryptophan Uptake Using [14C]tryptophan as a precursor, the intracellular localization o f indole-3-acetic acid biosynthesis in spinach mesophyll cells was investigated. Chloroplasts as well as extraplastidic compartments were able to transform tryptophan into indole-3-acetic acid. The cofactor requiremen...

Nitrite reduction in either whole, isolated spinach chloroplasts (Spinacia oleracea L.) or in reconstituted spinach chloroplasts is stimulated by a short period of photosynthetic CO(2) fixation in the light prior to nitrite addition. With reconstituted chloroplasts, a similar stimulation can be obtained in nitrite reduction without CO(2) fixation by the addition of dihydroxyacetone phosphate or...

Oxalic acid is widely distributed in plants. Although its concentration is not normally high, certain plants such as Oxalis sp., Begonia sp., rhubarb, and spinach contain large amounts of the acid. Cotyledons of spinach, for example, have been reported to contain up to 26% dry weight of oxalic acid (4). The only enzyme system previously reported to metabolize oxalate in plants is oxalate oxidas...

Aquaponics is a technique where recirculating aquaculture system (RAS) and hydroponics are integrated to grow plants fish in closed system. We investigated if the growth of rainbow trout (Oncorhynchus mykiss) baby spinach (Spinacia oleracea) would be affected coupled aquaponic compared RAS or hydroponic system, all systems as three replicates. also possible effects on onset nitrification biofil...

An enzyme-linked immunosorbent assay permitting the determination of nanogram quantities of nitrate reductase (NR) in cultured spinach cells has been developed and used for studies of the mechanism by which NR activity is regulated as a function of culture age. When 8-day old spinach cells were transferred to fresh medium, NR activity increased markedly in 2 days and thereafter decreased gradua...

Introduction Species of the genus Beta are recognized as sources of various viruses. A con­ siderable number o f viruses have been isolated from the species Beta vulgaris var. saccharifera (sugar beet) (Sutic et al. 1999). One of the viruses occurring in this plant all over the world is beet mosaic potyvirus (BtMV). This virus belongs to Potyviridae, a taxonomic family of easily aphid-transmitt...