David W KoenigKimberly-Clark Corporation · Life Sciences
David W Koenig
PHD
About
63
Publications
20,511
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1,277
Citations
Introduction
Additional affiliations
December 1997 - February 2022
November 1990 - December 1997
NASA , Houston, Texas
Position
- Senior Researcher
August 1988 - November 1990
Betz PaperChem, Jacksonville, FL
Position
- R&D Manager
Publications
Publications (63)
The conventional viewpoint of single-celled microbial metabolism fails to adequately depict energy flow at the systems level in host-adapted microbial communities. Emerging paradigms instead support that distinct microbiomes develop interconnected and interdependent electron transport chains that rely on cooperative production and sharing of bioene...
Urgency urinary incontinence (UUI) and overactive bladder (OAB) can both potentially be influenced by commensal and urinary tract infection-associated bacteria. The sensing of bladder filling involves interplay between various components of the nervous system, eventually resulting in contraction of the detrusor muscle during micturition. This study...
The skin of premature infants is underdeveloped rendering it more prone to break down and irritation. Therefore, special care is needed to protect premature skin and ensure it is not adversely affected. Many health care professionals advise using just water and cloth to clean diapered skin after a bowel movement despite evidence that shows improved...
Urgency urinary incontinence (UUI), the result of conditions such as overactive bladder (OAB), could potentially be influenced by both commensal and urinary tract infection-associated bacteria. The sensing of bladder filling involves interplay between various parts of the nervous system eventually resulting in contraction of the detrusor muscle dur...
Background
Obesity is known to modulate human health in a number of ways including altering the microbiome of the gut. Very few studies have examined the how obesity may affect the microbiomes of sites distant to the gut. We hypothesized that vulva and abdominal skin may be especially susceptible to body mass index (BMI)-induced alterations in biop...
While a part of the native gut microflora, the Gram-positive bacterium Enterococcus faecalis can lead to serious infections elsewhere in the body. The draft genome of E. faecalis strain ATCC BAA-2128, isolated from piglet feces, was examined. This draft genome consists of 42 contigs, 12 of which exhibit homology to annotated plasmids.
The actinobacterium Micrococcus luteus can be found in a wide variety of habitats. Here, we report the 2,411,958-bp draft genome sequence of the type strain M. leuteus (Schroeter) Cohn (ATCC 12698). Characteristic of this taxa, the genome sequence has a high G+C content, 73.14%.
A draft genome sequence for Escherichia coli ATCC 29425 was investigated. The size of the genome was 4,608,319 bp, with an observed G+C content of 50.68%. This assembly consisted of 80 contigs, with an average coverage of 122.2×, including one contig representative of the complete genome for the temperate phage P1.
Draft genome sequences for Staphylococcus aureus subsp. aureus Rosenbach ATCC 14458 and ATCC 27217 strains were investigated. The genome sizes were 2,880,761 bp and 2,759,100 bp, respectively. Strain ATCC 14458 was assembled into 39 contigs, including 3 plasmids, and strain ATCC 27217 was assembled into 25 contigs, including 2 plasmids.
Here, we report the draft genome sequence for the type strain Staphylococcus epidermidis (Winslow and Winslow) Evans (ATCC 14990). The assembly consisted of 2,457,519 bp with an observed G+C content of 32.04%. Thirty-seven contigs were produced, including two putative plasmids, with a 296.8× coverage and an N50 of 180,848 bp.
Here, we present the draft genome sequence of Escherichia coli ATCC 10798. E. coli ATCC 10798 is a K-12 strain, one of the most well-studied model microorganisms. The size of the genome was 4,685,496 bp, with a G+C content of 50.70%. This assembly consists of 62 contigs and the F plasmid.
The purpose of this study was to validate the use of adenosine triphosphate (ATP) for evaluating hygiene intervention effectiveness in reducing viral dissemination in an office environment. The bacterial virus MS-2 was used to evaluate two scenarios, one where the hand of an individual was contaminated and another where a fomite was contaminated. M...
Host-defense peptides (HDPs) are promising next generation of antibiotic agents, as they have the potential to circumvent emerging drug resistance, due to their mechanism of bacterial killing through disruption of their membranes. Nonetheless, HDPs have intrinsic drawbacks such as low-to-moderate activity, susceptibility to enzymatic degradation. I...
An assay was developed that tested the ability of Lactobacillus acidophilus to outcompete a challenge of Escherichia coli in a mixed culture containing different test nutrients. Using this assay, addition of fructo-oligosaccharide to the media allowed L. acidophilus to outcompete a challenge of E. coli, whereas in a mixed culture without the prebio...
This report describes fomite transmission of Staphylococcus aureus amongst various surfaces. A contact transfer protocol was completed to evaluate the movement of S aureus between a person wearing nitrile gloves and either: handshaking with another person with gloved hands, touching a plastic cellular telephone back, or touching a stainless steel r...
Viral illnesses like gastroenteritis and the common cold create a substantial burden in the workplace due to reduced productivity, increased absenteeism, and increased health care costs. Behaviors in the workplace contribute to the spread of human viruses via direct contact between hands, contaminated surfaces and the mouth, eyes, and/or nose. This...
Approximately 50% of norovirus cases in the United States occur in long-term care facilities; many incidences of rotavirus, sapovirus, and adenovirus also occur. The primary objectives of this study were to demonstrate movement of pathogenic viruses through a long-term care facility and to determine the impact of a hygiene intervention on viral tra...
Background
Natural moisturizing factor (NMF), principally comprised of hygroscopic amino acids and derivatives that absorb moisture from the surrounding environment, serves as the primary humectant of the stratum corneum (SC). Acute barrier disruption has been shown to differentially affect the concentration of NMF in the SC. This study measured th...
ABSTRACT Although the number of illnesses resulting from indirect viral pathogen transmission could be substantial, it is difficult to estimate the relative risks because of the wide variation and uncertainty in human behavior, variable viral concentrations on fomites, and other exposure factors. The purpose of this study was to evaluate the micro-...
The common occurrence of enteric bacteria in kitchen sponges and dishcloths suggests that they can play a role in the cross-contamination of foods, fomites and hands by foodborne pathogens. This study investigated the occurrence of bacteria in kitchen towels often used to dry dishes, hands and other surfaces in the domestic kitchen. A total of 82 k...
A lactobacilli dominated microbiota in most pre and post-menopausal women is an indicator of vaginal health. The objective of this double blinded, placebo-controlled crossover study was to evaluate in 14 post-menopausal women with an intermediate Nugent score, the effect of 3 days of vaginal administration of probiotic L. rhamnosus GR-1 and L. reut...
An oxidizing anti-microbial treatment and products containing such treatment are described. The treatment involves, in part, preparing a substrate to accept an attachment of charged moieties, and a number of stabilized peroxide compounds on at least part of a surface of said substrate. When microbes, such as bacteria, having a net charge opposite t...
The goals of this study were to observe the spread of viruses in a hotel setting and to assess the effectiveness of a hygiene intervention in reducing their spread. Selected fomites in one hotel room were inoculated with bacteriophage ϕx-174, and fomites in a conference center within the same hotel were inoculated using bacteriophage MS2. Cleaning...
Development of more effective products for cleansing the skin of microorganisms is enhanced by improved understanding of the mechanisms of attachment, as well as potential removal strategies. This paper describes an in vitro method for use of the cationic exchanger carboxymethylcellulose (CMC) to enhance the removal of the yeast Candida albicans as...
A self gassing composition comprising at least one surfactant and a fermentation base including a gas producing organism and at least one sugar is disclosed. Use of a nonionic surfactant in the self gassing composition allows the fermentation base to continue reacting and producing gas. Additionally, a personal care cleansing product and method for...
Objectives:
Natural moisturizing factor (NMF) serves as the primary humectant of the stratum corneum (SC), principally comprised of hygroscopic amino acids and derivatives that absorb moisture. Barrier disruption has been shown to differentially affect the levels of specific NMF components, though the kinetics of NMF component restoration followin...
The present disclosure comprises a polymeric substrate that provides multiple releases of active agents. A substrate for multiple phase delivery of active agents is provided having a first polymer matrix layer having a first active agent disposed therein, a second polymer matrix layer having a second active agent disposed therein, and a coacervate...
Methods to intercept bacterial quorum sensing (QS) have attracted significant attention as potential anti-infective therapies. Staphylococcus aureus is a major human pathogen that utilizes autoinducing peptide (AIP) signals to mediate QS and thereby regulate virulence. S. aureus strains are categorized into four groups (I-IV) according to their AIP...
Background:
Health care-associated infections (HAIs) are a significant problem in hospitals, and environmental surfaces have been implicated as a source of HAIs in the hospital environment. Furthermore, Gram-negative and Gram-positive bacteria can persist on dry environmental surfaces for as long as several months. Poorly cleaned surfaces may serv...
Background:
Hospital cleaning practices are critical to the prevention of nosocomial infection transmission. To this end, cloth towels soaked in disinfectants are commonly used to clean and disinfect hospital surfaces. Cloth cleaning towels have been linked to an outbreak of Bacillus cereus and have been shown to reduce the effectiveness of common...
The stratum corneum (SC) is a complex structure that protects our bodies and makes it possible for mammalian life on this planet. The SC employs a combination of both physical and biochemical processes to limit the movement of water in and out of the body although clearly it is the latter that is of most importance. The SC can be disturbed by compa...
The ideal gentle cleansing product is one that effectively removes soils while minimizing damage to the skin. Thus, measuring physical abrasion caused by cleansing tissues is critical to the continued development of gentle cleansing products. Current analysis of cleansing materials for skin gentleness is time consuming and requires expensive human...
Affymetrix read outs for 960 probe sets representing those differentially expressed by at least 2-fold.
(PDF)
Relative abundances of each OTU for samples at time point 0 with and without vaginal dryness. Each plot represents a single OTU and the relative abundance (fraction of microbiota) for each time point 0 sample is plotted on the y-axis. The samples are divided into two groups based on the nurse's observation: women without vaginal dryness (none or mi...
Taxonomic assignments to OTUs at ≥1% relative abundance in any one sample. Assignments were made using the Greengenes database [32] and manually validated by BLAST [39] to the NCBI non-redundant database.
(PDF)
A heatmap representing the scored vaginal dryness and atrophy. The symptoms were self-reported by the participants via a questionnaire, and also reported as observed by the nurse upon examination of the vagina. Atrophy was an overall subjective score by the nurse based on all clinical observations, smoothness was scored as a lack of rugosity, irrit...
After menopause, many women experience vaginal dryness and atrophy of tissue, often attributed to the loss of estrogen. An understudied aspect of vaginal health in women who experience dryness due to atrophy is the role of the resident microbes. It is known that the microbiota has an important role in healthy vaginal homeostasis, including maintain...
Relatively little has been done to investigate the impact of season and/or climate on skin biochemistry. The objective of this work was to investigate differences in skin biochemistry across two climates using in vivo Raman confocal spectroscopy. The study spanned summer to winter in Neenah, WI and Dallas, TX. Daily temperature and dew point were r...
Production of irritants by microbes on or near the skin's surface may lead to skin inflammation as well as offensive odors. A mannitol hydrogen peroxide (MHP) mixture was found to reduce the production of skin irritating compounds by facultative Gram-negative bacteria. This control method appears to influence metabolic regulation rather than impact...
A partir de la souche sauvage de Lipomyces strakeyi un mutant permettant la synthese de dextranases est fabrique. Differents sucres induisant la formation de l'enzyme sont testes, un seul est retenu et avec celui-ci, l'apparition de l'activite dextranase induite est mesuree en fonction du temps. Un transfert a des fermenteurs de tres grands volumes...
Pseudomonas syringae pathovar phaseolicola, which produces alginate during stationary growth phase, displayed elevated extracellular alginate lyase activity during
both mid-exponential and late-stationary growth phases of batch growth. Intracellular activity remained below 22% of the total
activity during exponential growth, suggesting that alginat...
The microgravity environment of space introduces a major new variable for consideration that will affect the design and operation of bioreactors. Adequate aeration for aerobic bioreactors will be a challenge as will gas/liquid separation, removal of carbon dioxide and other bacterial metabolic waste products, control algorithms, and overall perform...
The Space Shuttle has a once-through water system that is initially filled on the ground, partially drained before launch and then refilled with fuel-cell generated water on orbit. The microbiological standard for the Space Shuttle potable water system during this study period allowed only 1 microbe of any kind per l00mL and no detectable coliforms...
Production of the antibacterial polypeptide microcin B17 (MccB17) by Escherichia coli ZK650 was inhibited by simulated microgravity. The site of MccB17 accumulation was found to be different, depending on whether the organism was grown in shaking flasks or in rotating bioreactors designed to establish a simulated microgravity environment. In flasks...
The first two phases of the Lunar-Mars Life Support Test Project [LMLSTP] involved housing human volunteers in closed chambers that mimic future extraterrestrial life support systems. The Phase I test involved one person living for 15 days in a chamber with wheat as the primary means of air revitalization. The Phase II test involved 4 people living...
The Space Shuttle has a once-through water system that is initially filled on the ground, partially drained before launch and then refilled with fuel-cell generated water on orbit. The microbiological standard for the Space Shuttle potable water system during this study period allowed only 1 microbe of any kind per 100mL and no detectable coliforms...
In a continuing study of microbial secondary metabolism in
simulated microgravity, we have examined gramicidin S (GS) production by
Bacillus brevis strain Nagano in NASA High Aspect Rotating Vessels
(HARVs), which are designed to simulate some aspects of microgravity. Growth
and GS production were found to occur under simulated microgravity. When
p...
The goal of this study was to characterize sessile and planktonic microbiota that developed during two successive hydroponic cultures of lettuce in a closed chamber system. Coupons of polyvinyl chloride (PVC) placed in the nutrient solution lines were removed periodically, as were samples of the nutrient solutions and condensate from the air-handli...
Rotating bioreactors designed at NASA's Johnson Space Center were used to simulate a microgravity environment in which to study secondary metabolism. The system examined was beta-lactam antibiotic production by Streptomyces clavuligerus. Both growth and beta-lactam production occurred in simulated microgravity. Stimulatory effects of phosphate and...
Iodine is used to disinfect the water system aboard US space shuttles and is the anticipated biocide for the international space station. Water quality on spacecraft must be maintained at the highest possible levels for the safety of the crew. Furthermore, the treatment process used to maintain the quality of water on research must be robust and op...
A Variable Pressure Plant Growth Chamber (VPGC), at the Johnson Space Center's (JSC) ground-based Regenerative Life Support Systems (RLSS) test bed, was used to produce crops of soil-grown lettuce. The crops and chamber were analyzed for microbiological diversity during lettuce growth and after harvest. Bacterial counts for the rhizosphere, spent n...
Lipomyces starkeyi ATCC 20825 is a derepressed mutant derived from L. starkeyi ATCC 12659. It requires the presence of an inducer before it produces dextranase. This study was undertaken to determine the most efficient, commercially feasible method for inducing this enzyme. The following compounds induced dextranase synthesis: 1-O-beta-methyl-gluco...
Dextranase produced by Lipomyces starkeyi was purified 43-fold, by carboxymethyl-Sepharose chromatography followed by agarose gel-filtration chromatography. The purified enzyme showed four bands by SDS/polyacrylamide gel electrophoresis with estimated mass 74 kDa, 71 kDa, 68 kDa and 65 kDa. This preparation exhibited multiple isoelectric points bet...
The optimal growth rate ofLipomyces
starkeyi, with dextran as sole carbon source, was found within the pH range 2.5–4.0, and temperature between 25–30°C. This yeast was unable to grow above 33°C. Dextranase production optima paralleled growth optima, except at pH 2.5. Decrease in enzyme yield at this pH could not be attributed to poor yeast growth...
Strain UMK-13 of the achlorophyllous alga Prototheca zopfii Krüger was tested for itsability to grow on crude-oil under a variety of conditions of pH, temperature, and salinity representing various aquatic habitats. Biodegradation of 13-16 carbon and 20-21 carbon n-alkanes occurred within a pH range of 3-9, at 8-24 parts per thousand salinity, and...
A new strain of Prototheca zopfii Krüger was grown on acetate or on pure n-alkanes. A maximum acetate-supported exponential growth of 12 divisions day occurred at pH 5 and 30 degrees C. At 25 degrees C, growth on n-alkanes was almost as fast, but no growth occurred at 30 degrees C. After 4 days at 25 degrees C, 34 to 45% of the n-alkanes had been r...