Genomic and proteomic characterization of Gordonia sp. NB4-1Y in relation to 6 : 2 fluorotelomer sulfonate biodegradation.

Gordonia sp. strain NB4-1Y was isolated from vermicompost using bis-(3-pentafluorophenylpropyl)-sulfide as the sole added sulfur source and was found to have a broad capacity for metabolizing organosulfur compounds. NB4-1Y is closely related to G. desulfuricans and was found to metabolize 6 : 2 fluorotelomer sulfonate (6 : 2 FTS) to 5 : 3 fluorotelomer acid (5 : 3 acid) via 6 : 2 fluorotelomer acid (6 : 2 FTCA), 6 : 2 unsaturated fluorotelomer acid (6 : 2 FTUCA) and 5 : 3 unsaturated fluorotelomer acid (5 : 3 Uacid). Given that the molecular and biochemical basis for the microbial metabolism of poly- and per-fluorinated compounds has yet to be examined, we undertook to investigate 6 : 2 FTS metabolism in NB4-1Y. To this end, a whole-genome shotgun sequence was prepared and two-dimensional differential in-gel electrophoresis was used to compare proteomes of MgSO4- and 6 : 2 FTS-grown cells. Of the three putative alkanesulfonate monooxygenases, four nitrilotriacetate monooxygenases and one taurine dioxygenase located in the draft genome, two nitrilotriacetate monooxygenases were differentially expressed in the presence of 6 : 2 FTS. It is hypothesized that these two enzymes may be responsible for 6 : 2 FTS desulfonation. In addition, a differentially expressed putative double bond reductase may be involved in the reduction of 5 : 3 Uacid to 5 : 3 acid. Other proteins differentially expressed during 6 : 2 FTS metabolism included a sulfate ABC transporter ATP-binding protein and two alkyl hydroperoxide reductases. This work establishes a foundation for future studies on the molecular biology and biochemistry of poly- and per-fluorinated compound metabolism in bacteria.

Assessing the engagement, learning, and overall experience of students operating an atomic absorption spectrophotometer with remote access technology.

The use of internet-based technologies in the teaching of laboratories has emerged as a promising education tool. This study evaluated the effectiveness of using remote access technology to operate an atomic absorption spectrophotometer in analyzing the iron content in a crude myoglobin extract. Sixty-two students were surveyed on their level of engagement, learning, and overall experience. Feedback from students suggests that the use of remote access technology is effective in teaching students the principles of chemical analysis by atomic absorption spectroscopy.

Integrating bio-inorganic and analytical chemistry into an undergraduate biochemistry laboratory.

Undergraduate laboratories expose students to a wide variety of topics and techniques in a limited amount of time. This can be a challenge and lead to less exposure to concepts and activities in bio-inorganic chemistry and analytical chemistry that are closely-related to biochemistry. To address this, we incorporated a new iron determination by atomic absorption spectroscopy exercise as part of a five-week long laboratory-based project on the purification of myoglobin from beef. Students were required to prepare samples for chemical analysis, operate an atomic absorption spectrophotometer, critically evaluate their iron data, and integrate these data into a study of myoglobin.