Day 2 :
Keynote Forum
Rajesh Sani
South Dakota School of Mines and Technology, USA
Keynote: An Overview of Thermophilic Bioprocessing of Solid Wastes to Biofuels
Time : 9:45-10:30
Biography:
Rajesh Sani is an Associate Professor in the Department of Chemical and Biological Engineering at South Dakota School of Mines and Technology, USA. His
research includes extremophilic bioprocessing of lignocellulose-based renewable for biofuels and bioproducts and bioprospecting of extremophilic microorganisms
for developing more effi cient and cost-effective biofuel (bioenergy) production technologies. Over the past 10 years, he has been the PI or Co-PI on over $10.5
million in funded research. He has one patent, fi ve invention disclosures and published 50 peer-reviewed articles in high impact factor journals and has contributed
in several book chapters. In addition, he has been a proposal Reviewer and Panelist for the Federal Agencies and also serves the Industrial Microbiology profession
as “Biocatalysis Program Committee Member” of the Society for Industrial Microbiology and Biotechnology (SIMB), Technical Session Chair at the Annual American
Institute of Chemical Engineers (AIChE) and SIMB, and is also an Associate Editor.
Abstract:
Management and complete disposal of 2G solid waste including lignocellulosic biomass is an ever increasing concern
in current scenario. Available chemical and biological technologies have several shortcomings. For example, corequirement
of expensive pretreatment step, undesired synthesis of hazardous byproducts, and emission of toxic gases and
effl uents are few to list. Development of an ecofriendly technique which can be operated at low capital investment and produce
bioenergy would be a real solution for the solid waste disposal. Th ermophiles and their enzymes can play important roles
in many kinds of bioprocessing. Th is talk will describe the limitations in exiting 2G feedstock conversion technologies and
possible ways to overcome those limitations using thermophiles and their enzymes. Th e infl uence of high temperatures on
various existing 2G feedstock conversion processes and those that are under development, including separate hydrolysis and
fermentation, simultaneous saccharifi cation and fermentation, and extremophilic consolidated bioprocess will discussed.
Integrated decentralized thermophilic biofuel production employing hydrolytic- and fermentative-thermophiles in a single
step consolidated process will also be discussed.
Keynote Forum
Choong-Min Kang
California State University, USA
Keynote: Reduction of feedback inhibition in homoserine kinase (ThrB) enhances the L-threonine biosynthesis
Time : 11:20-11:50
Biography:
Choong-Min Kang has completed his PhD in Microbiology from UC Davis and Postdoctoral studies from Children’s Hospital Boston, Harvard Med School. He is
currently an Associate Professor at California State University, USA. He has published more than 27 papers in reputed journals.
Abstract:
L-threonine is a limiting amino acid in livestock diets and its defi ciency results in not only malnutrition of the animals
but also releasing increased volumes of nitrogen compounds to the environment. Addition of L-threonine into livestock
feed is therefore important for healthier animals as well as a cleaner environment. Moreover, L-threonine is utilized in both
pharmaceutical and cosmetic industries. Currently, L-threonine is produced by E. coli, which makes the purifi cation of
L-threonine diffi cult because it produces endotoxins. Th us, we seek to over-produce L-threonine by using Corynebacterium
glutamicum, a GRAS (generally regarded as safe) microorganism. C. glutamicum produces L-threonine from aspartate
through an enzymatic pathway involving aspartate kinase (LysC), aspartate semialdehyde dehydrogenase (Asd), homoserine
dehydrogenase (Hom), homoserine kinase (Th rB) and threonine synthase (Th rC). Among these, LysC, Hom and Th rB are
feedback inhibited by the end-product, L-threonine. Releasing the feedback inhibition in LysC and Hom through mutating their
allosteric site has successfully increased L-threonine biosynthesis. However, it has been unsuccessful to remove the feedback
inhibition in Th rB because L-threonine inhibits the enzyme by competing with L-homoserine (substrate) for the same active
site. To genetically separate the catalytic activity and the feedback inhibition in Th rB of C. glutamicum, we mutated a residue
at the gate of the active site into various amino acids such as hydrophobic residues (Leu and Val) and hydrophilic residue (Ser
and Gly). Enzymatic kinetics with the wild-type and mutant forms of Th rB showed that one specifi c mutation increased Ki
for L-Th reonine about 5-fold while it increased Km for homoserine only 2-fold. More importantly, when we introduced this
mutation into C. glutamicum and E. coli, it increased approximately 20% of L-threonine production. Our approach can be
applied to other metabolic enzymes that are similarly regulated by competitive feedback inhibition.
Keynote Forum
Rajesh Sani
South Dakota School of Mines and Technology, USA
Keynote: Extremophiles in biofuel synthesis from solid wastes
Time : 11:50-12:20
Biography:
Rajesh Sani is an Associate Professor in the Department of Chemical and Biological Engineering at South Dakota School of Mines and Technology, USA. His
research includes extremophilic bioprocessing of lignocellulose-based renewable for biofuels and bioproducts and bioprospecting of extremophilic microorganisms
for developing more effi cient and cost-effective biofuel (bioenergy) production technologies. Over the past 10 years, he has been the PI or Co-PI on over $10.5
million in funded research. He has one patent, fi ve invention disclosures and published 50 peer-reviewed articles in high impact factor journals and has contributed
in several book chapters. In addition, he has been a proposal Reviewer and Panelist for the Federal Agencies and also serves the Industrial Microbiology profession
as “Biocatalysis Program Committee Member” of the Society for Industrial Microbiology and Biotechnology (SIMB), Technical Session Chair at the Annual American
Institute of Chemical Engineers (AIChE) and SIMB and is also an Associate Editor.
Abstract:
More than 34% of a typical solid waste are food, wood and yard waste whereas paper and paperboard contribute to another
25% to the ever increasing issue of waste management and its disposal. To date physiochemical pretreatment of solid
wastes has been shown a necessary step for previously listed consolidated biological processes which increases the overall cost
of the process e.g., plant biomass is inexpensive ($2-4/GJ at a cost of $39-60/dry ton biomass) but its pretreatment cost ($15-25/
GJ) dramatically reduce the overall cost-effi ciency of the process. An alternative to the bioprocess involving pretreatment is the
development of an effi cient and cost-eff ective single step process for untreated solid waste management using extremophiles.
For example, thermophiles and their enzymes can play important roles in many kinds of bioprocessing including in conversion
of non-food biomass into biofuels. Th e Homestake gold mine (8000 ft . deep, Lead, SD) off ers a unique opportunity for direct
exploration of the deep biosphere environment. Using soil/biofi lm samples of deep biosphere of the Homestake Gold Mine,
compost facility (Rapid City, SD) and Hot Springs State Park (Th ermopolis WY), we have isolated several thermophilic
cellulose and xylan-degrading and fermenting pure cultures belonging to the genera Brevibacillus, Paenibacillus, Clostridium,
Bacillus and Geobacillus. Unique characteristics of lignocellulose-deconstructing enzymes produced by mine and compostthermophiles
include optimum temperatures of >70ºC, pH ranges from 4-8 and high thermostability (e.g., at 60ºC, 50%
of cellulases and xylanases activities were retained in 35 and 23 days of incubation, respectively). Our thermophiles also
produced biohydrogen or bioethanol in a single step bioprocessing of various inexpensive regional untreated biomass (e.g.,
prairie cord grass and corn stover). Th is talk will describe the limitations in exiting solid waste conversion technologies and
possible ways to overcome those limitations using thermophiles and their enzymes. Th e infl uence of high temperatures on
various existing lignocellulose conversion processes and those that are under development, including separate hydrolysis
and fermentation, simultaneous saccharifi cation and fermentation and extremophilic consolidated bioprocess will discussed.
Integrated decentralized thermophilic biofuel production employing cellulolytic and fermentative thermophiles in a single
step consolidated process will also be discussed.
Keynote Forum
Eman M Khalaf
University of Guelph, Canada
Keynote: Taxonomic diversity of cucurbit seed associated endophytes
Time : 12:50-13:20
Biography:
Eman M Khalaf has completed her BSc and PhD from Pharmacy School, Mansoura University, Egypt. She is presently working as a Lecturer of Microbiology,
Pharmacy School, Damanhour University, Egypt. She has spent two years as a Postdoctoral fellow in Raizada Lab (Benefi cial Microbes Lab), University of Guelph,
Canada
Abstract:
Endophytes are potentially benefi cial microbes that live inside plants and can be utilized as biofertilizers and biocontrol
agents by promoting plant growth and/or suppressing phytopathogens. Few endophytes have previously been isolated
from the cucurbit plant family which includes economically important crops including watermelon, cucumber, cantaloupe,
pumpkin and squash. In the present study, 169 bacterial endophytes and 10 fungal endophytes were isolated from seeds of
diff erent varieties of diverse cucurbits; the most comprehensive characterization of endophytes from this plant family. 16S
rDNA and internal transcribed spacers (ITS4 and ITS1F) fi ngerprinting were used to taxonomically classify the isolated
bacteria and fungi, respectively. Phylogenetic analysis of bacterial isolates showed Bacilli was the most abundant class including
six diff erent bacterial families. Th e γ-proteobacteria and Actinobacteria were also represented in four diff erent families. Bacillus
was the core microbiota that was conserved across tested cucurbits genera. Strains of the genus Paenibacillus were exclusively
isolated from Cucumis sativus L, Cucumis melo L and Cucurbita pepo L. var pepo L. Th ree diff erent genera of lactic acid bacteria
(LAB) were recovered from C. sativus L, C. melo L., Citrullus lanatus var. lanatus and Cucurbita pepo L var. turbinata. Our
results suggest co-evolution of seed microbial consortia with their host plants. We now propose to test these novel endophytic
microbial strains for their ability to suppress important fungal and bacterial pathogens of the cucurbit family.
- Microbes Potential Uses|Industrial Applications of Microbes|Environmental Microbiology|Applications of Extremophiles
Chair
Choong-Min Kang
California State University, USA
Co-Chair
Eman M Khalaf
University of Guelph, Canada
Session Introduction
Choong-Min Kang
California State University, USA
Title: Reduction of feedback inhibition in homoserine kinase (ThrB) enhances the L-threonine biosynthesis
Time : 11:20-11:50
Biography:
Choong-Min Kang has completed his PhD in Microbiology from UC Davis and Postdoctoral studies from Children’s Hospital Boston, Harvard Med School. He is
currently an Associate Professor at California State University, USA. He has published more than 27 papers in reputed journals.
Abstract:
L-threonine is a limiting amino acid in livestock diets and its defi ciency results in not only malnutrition of the animals
but also releasing increased volumes of nitrogen compounds to the environment. Addition of L-threonine into livestock
feed is therefore important for healthier animals as well as a cleaner environment. Moreover, L-threonine is utilized in both
pharmaceutical and cosmetic industries. Currently, L-threonine is produced by E. coli, which makes the purifi cation of
L-threonine diffi cult because it produces endotoxins. Th us, we seek to over-produce L-threonine by using Corynebacterium
glutamicum, a GRAS (generally regarded as safe) microorganism. C. glutamicum produces L-threonine from aspartate
through an enzymatic pathway involving aspartate kinase (LysC), aspartate semialdehyde dehydrogenase (Asd), homoserine
dehydrogenase (Hom), homoserine kinase (Th rB) and threonine synthase (Th rC). Among these, LysC, Hom and Th rB are
feedback inhibited by the end-product, L-threonine. Releasing the feedback inhibition in LysC and Hom through mutating their
allosteric site has successfully increased L-threonine biosynthesis. However, it has been unsuccessful to remove the feedback
inhibition in Th rB because L-threonine inhibits the enzyme by competing with L-homoserine (substrate) for the same active
site. To genetically separate the catalytic activity and the feedback inhibition in Th rB of C. glutamicum, we mutated a residue
at the gate of the active site into various amino acids such as hydrophobic residues (Leu and Val) and hydrophilic residue (Ser
and Gly). Enzymatic kinetics with the wild-type and mutant forms of Th rB showed that one specifi c mutation increased Ki
for L-Th reonine about 5-fold while it increased Km for homoserine only 2-fold. More importantly, when we introduced this
mutation into C. glutamicum and E. coli, it increased approximately 20% of L-threonine production. Our approach can be
applied to other metabolic enzymes that are similarly regulated by competitive feedback inhibition.
Rajesh Sani
South Dakota School of Mines and Technology, USA
Title: Extremophiles in biofuel synthesis from solid wastes
Time : 11:50-12:20
Biography:
Rajesh Sani is an Associate Professor in the Department of Chemical and Biological Engineering at South Dakota School of Mines and Technology, USA. His
research includes extremophilic bioprocessing of lignocellulose-based renewable for biofuels and bioproducts and bioprospecting of extremophilic microorganisms
for developing more effi cient and cost-effective biofuel (bioenergy) production technologies. Over the past 10 years, he has been the PI or Co-PI on over $10.5
million in funded research. He has one patent, fi ve invention disclosures and published 50 peer-reviewed articles in high impact factor journals and has contributed
in several book chapters. In addition, he has been a proposal Reviewer and Panelist for the Federal Agencies and also serves the Industrial Microbiology profession
as “Biocatalysis Program Committee Member” of the Society for Industrial Microbiology and Biotechnology (SIMB), Technical Session Chair at the Annual American
Institute of Chemical Engineers (AIChE) and SIMB and is also an Associate Editor.
Abstract:
More than 34% of a typical solid waste are food, wood and yard waste whereas paper and paperboard contribute to another
25% to the ever increasing issue of waste management and its disposal. To date physiochemical pretreatment of solid
wastes has been shown a necessary step for previously listed consolidated biological processes which increases the overall cost
of the process e.g., plant biomass is inexpensive ($2-4/GJ at a cost of $39-60/dry ton biomass) but its pretreatment cost ($15-25/
GJ) dramatically reduce the overall cost-effi ciency of the process. An alternative to the bioprocess involving pretreatment is the
development of an effi cient and cost-eff ective single step process for untreated solid waste management using extremophiles.
For example, thermophiles and their enzymes can play important roles in many kinds of bioprocessing including in conversion
of non-food biomass into biofuels. Th e Homestake gold mine (8000 ft . deep, Lead, SD) off ers a unique opportunity for direct
exploration of the deep biosphere environment. Using soil/biofi lm samples of deep biosphere of the Homestake Gold Mine,
compost facility (Rapid City, SD) and Hot Springs State Park (Th ermopolis WY), we have isolated several thermophilic
cellulose and xylan-degrading and fermenting pure cultures belonging to the genera Brevibacillus, Paenibacillus, Clostridium,
Bacillus and Geobacillus. Unique characteristics of lignocellulose-deconstructing enzymes produced by mine and compostthermophiles
include optimum temperatures of >70ºC, pH ranges from 4-8 and high thermostability (e.g., at 60ºC, 50%
of cellulases and xylanases activities were retained in 35 and 23 days of incubation, respectively). Our thermophiles also
produced biohydrogen or bioethanol in a single step bioprocessing of various inexpensive regional untreated biomass (e.g.,
prairie cord grass and corn stover). Th is talk will describe the limitations in exiting solid waste conversion technologies and
possible ways to overcome those limitations using thermophiles and their enzymes. Th e infl uence of high temperatures on
various existing lignocellulose conversion processes and those that are under development, including separate hydrolysis
and fermentation, simultaneous saccharifi cation and fermentation and extremophilic consolidated bioprocess will discussed.
Integrated decentralized thermophilic biofuel production employing cellulolytic and fermentative thermophiles in a single
step consolidated process will also be discussed.
Eman M Khalaf
University of Guelph, Canada
Title: Taxonomic diversity of cucurbit seed associated endophytes
Time : 12:20-12:50
Biography:
Eman M Khalaf has completed her BSc and PhD from Pharmacy School, Mansoura University, Egypt. She is presently working as a Lecturer of Microbiology,
Pharmacy School, Damanhour University, Egypt. She has spent two years as a Postdoctoral fellow in Raizada Lab (Benefi cial Microbes Lab), University of Guelph,
Canada
Abstract:
Endophytes are potentially benefi cial microbes that live inside plants and can be utilized as biofertilizers and biocontrol
agents by promoting plant growth and/or suppressing phytopathogens. Few endophytes have previously been isolated
from the cucurbit plant family which includes economically important crops including watermelon, cucumber, cantaloupe,
pumpkin and squash. In the present study, 169 bacterial endophytes and 10 fungal endophytes were isolated from seeds of
diff erent varieties of diverse cucurbits; the most comprehensive characterization of endophytes from this plant family. 16S
rDNA and internal transcribed spacers (ITS4 and ITS1F) fi ngerprinting were used to taxonomically classify the isolated
bacteria and fungi, respectively. Phylogenetic analysis of bacterial isolates showed Bacilli was the most abundant class including
six diff erent bacterial families. Th e γ-proteobacteria and Actinobacteria were also represented in four diff erent families. Bacillus
was the core microbiota that was conserved across tested cucurbits genera. Strains of the genus Paenibacillus were exclusively
isolated from Cucumis sativus L, Cucumis melo L and Cucurbita pepo L. var pepo L. Th ree diff erent genera of lactic acid bacteria
(LAB) were recovered from C. sativus L, C. melo L., Citrullus lanatus var. lanatus and Cucurbita pepo L var. turbinata. Our
results suggest co-evolution of seed microbial consortia with their host plants. We now propose to test these novel endophytic
microbial strains for their ability to suppress important fungal and bacterial pathogens of the cucurbit family.